Hi drfkv5,

Welcome to Microsoft Answers Forum.

As you are using a wireless keyboard I would suggest you to check on the F LOCK (function lock) key on your keyboard. Check on the top right of your Keyboard for the F Lock Key, which may be stopping you from using the print screen key. The F LOCK key toggles the alternate function keys. An alternate function key is a key that has two possible commands depending on the F LOCK toggle key state.

Check the below Microsoft article for details:

http://support.microsoft.com/kb/894513

Also try and check if the status light on the keyboard for the F LOCK key. Refer to the below article for help on status light identification:

http://support.microsoft.com/kb/894037

To add on, I would suggest you to try the snipping tool in Windows7. It can help you take the screen shots easily. You can check the snipping tool functionality with the help of these articles:

http://windows.microsoft.com/en-us/windows7/products/features/snipping-tool

http://windows.microsoft.com/en-us/windows7/Use-Snipping-Tool-to-capture-screen-shots

Thanks, 
Hope this helps. Let us know the results.
Meghmala – Microsoft Support

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