Do you own a Netbook without a CD/DVD drive, but want to install Windows 7 on it? No problem! Microsoft has made available a tool known as Windows 7 USB/DVD Download Tool, which takes an ISO image and creates a bootable USB device that can be used to install Windows 7. The utility can create a Windows 7 installation DVD from the ISO file as well.
Update (Nov 10, 2009): Microsoft pulls download tool over GPL violation accusation

Download Windows 7 USB/DVD Download Tool from Microsoft Store Website. To copy the ISO image to USB flash drive, ensure that the drive has minimum 4 GB of free space.
Additional Note
The tool works only for the Windows 7 ISO image downloaded from online Microsoft Store. It throws the following error if you use a custom Windows 7 ISO image.
The selected file is not a valid ISO file. Please select a valid ISO file and try again.
However, Rafael Rivera of Within Windows has written a tool that will allow you to use your own ISOs with the Windows 7 USB/DVD Download Tool. For more information, read the excellent post Use the Windows 7 USB/DVD Download Tool with custom ISOs by Rafael.
Windows 7 does not include a GUI to disable the taskbar thumbnail preview feature. I’ve experimented with the registry setting TaskbarNoThumbnail and its equivalent GPO Turn off taskbar thumbnails. That setting seems to apply only to Windows Vista, and has no effect in Windows 7.

You can however disable the taskbar thumbnail feature (sort of) in Windows 7 using a registry edit. This can be done by setting the taskbar thumbnail preview hover delay to a large value (say 10000 milliseconds or more), so that the preview is not immediately generated when you hover over a taskbar icon. Well. Then the article title should have really been "How To Delay Taskbar Thumbnail Preview in Windows 7".
I heard about this registry value via article Adjust Taskbar Preview Hover Delay at WinGeek.com (Credits to Steve Sinchak), and experimented the registry value by inputting a large decimal value to prevent immediate display of thumbnails in the Windows 7 Taskbar.
1. Click Start, type Regedit.exe and press {ENTER}
2. Navigate to the following location:
HKEY_CURRENT_USER \ Software \ Microsoft \ Windows \ CurrentVersion \ Explorer \ Advanced
3. Create a new DWORD (32-bit) value named ExtendedUIHoverTime
4. Double-click ExtendedUIHoverTime and click Decimal
5. To increase the hover delay to 5 seconds, type 5000. Type 10000 for 10 seconds and so forth…

6. Exit the Registry Editor.
7. Logoff and login back, or restart the Shell ("Exit Explorer" method).
Related Article
Adjusting Aero Peek Desktop Preview Mouse Hover Delay in Windows 7.
When you double-click a library to view the contents, the following error may occur.
"<libraryname>.library-ms" is no longer working.
For example, the following error may occur when opening Documents library
"Documents.library-ms" is no longer working.
This library can be safely deleted from your computer. Folders that have been included will not be affected.

Similarly when opening the Music, Pictures or Videos library
"Music.library-ms" is no longer working.
"Pictures.library-ms" is no longer working.
"Videos.library-ms" is no longer working.
To fix this problem, open Windows Explorer, right-click on the corresponding library and choose Delete. Click Yes when asked for confirmation.
Note: Deleting a library does not delete the contents of the included folders. However, you may need to re-add or include your folders manually, if needed.
Then, in the navigation pane of Windows Explorer, right-click Libraries and click Restore default libraries.

This recreates the library that was deleted earlier. This option only restores the default libraries.
The Windows 7 Product Guide provides a detailed look at the many new and improved features in Windows 7. The guide is designed as an accurate source of information that can help you to understand how Windows 7 Simplifies Everyday Tasks, Works the Way You Want, and Makes New Things Possible. The guide is also designed to provide IT Professionals with information about how to Make People Productive Anywhere, Manage Risk Through Enhanced Security and Control, and Reduce Costs by Streamlining PC Management. This is not a help and how to guide. Rather, it provides an overview of the many exciting features in Windows 7 and pointers to more information. The Windows 7 Product Guide is available in both XPS and PDF formats.

Download Windows 7 Product Guide (via The Windows Team Blog)
Windows XP Mode is a new Windows 7 feature that lets you run older Windows XP applications on your Windows 7 desktop. Windows XP Mode is available for the Professional and Ultimate editions of Windows 7.
In order to use the Windows XP Mode in Windows 7, your system must support hardware virtualization (and also the option should be enabled in the BIOS). The Microsoft® Hardware-Assisted Virtualization Detection Tool (HAV detection tool) helps you check if your computer processor supports HAV. The tool also checks if this setting is enabled for the processor.

References
How to confirm your PC can run Windows XP Mode
Download: Windows XP Mode & Windows Virtual PC
System Requirements: Windows Virtual PC
In Windows Vista, turning off the Tablet PC Components also removes the Snipping Tool. This is not the case in Windows 7, where the Snipping Tool is integrated with the Operating System.

Fig 1: Windows Features dialog box in Windows Vista. (See InfoTip)

Fig 2: Windows Features dialog box in Windows 7. (See InfoTip)
Those who use the Snipping Tool but don’t use other Tablet PC features, can remove Tablet PC Components with no problems.
Note: Snipping Tool is available only in the Home Premium, Professional, and Ultimate editions of Windows 7.
Do you own a old hardware (for example printer, scanner, or any other device) or software and want to check its compatibility with Windows 7? Apart from using the Windows 7 Upgrade Advisor, there is an excellent online resource which tells you whether a software or hardware is compatible with Windows 7 or not. It’s the Windows 7 Compatibility Center which list thousands of products and clearly label their compatibility status for Windows 7.
I used the Windows 7 Upgrade Advisor before upgrading a computer running Windows Vista. The Upgrade Advisor had no compatibility information about the HP Deskjet 3745 Printer which was connected to the system.

Then I visited the Windows 7 Compatibility Center and looked up compatibility information for HP Deskjet 3745. It was listed as compatible.

Clicking the Learn more link provided the driver download URL (linking to manufacturer’s site.)
Editor’s note: The Windows 7 Compatibility Center uses five different icons so you can identify a product’s compatibility status. To know what each icon means, read Question #3 in Windows 7 Compatibility Center FAQ.
After installing or upgrading to Windows 7, you may notice that the AutoPlay dialog does not list Windows Media Center as one of the options.

This is the case when you open Change AutoPlay settings applet in Control Panel.

Windows 7 does not seem to include the Windows Media Center AutoPlay registry entries by default. However, you can add the necessary entries manually or export the keys from a Windows Vista PC (which is what I did). The AutoPlay entries are populated from this registry branch:
HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows \ CurrentVersion \ explorer \ AutoplayHandlers
Tip: Keys and Values starting with the word "EHome" (EHomeDVDDropTarget, EHomeMusicDropTarget, EHomePhotosHandler, EHomeSVCDDropTarget, EHomeVCDDropTarget, EHomeVideosHandler) are the ones we need.
I’ve made available a REG file which adds all of the Windows Media Center AutoPlay handler entries to the registry.
Registry Fix
Download w7-ehome-autoplay.zip, and save to Desktop. Unzip and run the enclosed REG file.

Windows Media Center is now added to the AutoPlay dialog!

Edison is an excellent power management tool made for Microsoft Windows XP and Windows Vista systems. Edison optimizes Windows Power Management settings for maximum power savings and provides a friendly user interface to configure the power settings.
Download Edison from Verdiem’s Website. (See also Verdiem :: Edison FAQ.)

Alter the Work Time Power Settings by moving the slider. To input custom values (hours: minutes) click the Custom button. And, click the Schedule tab and set your Work Time.
Edison creates a custom power plan, which can be viewed using Power Options (Windows Vista).

Edison changes the power plan options automatically, based on Work Time and Non-Work Time settings.

Microsoft has made available several fun extras to give your PC a personal touch. These extras include new desktop themes, backgrounds and gadgets for Windows 7. Visit the Personalization Gallery to download them.

(via The Windows Club)
Want to create our own theme, check out this guide.