Keyboard Problem

Need some help please!

Don't know how it happened, but 2 weeks ago my keyboard enter (return) key is acting wierd.
Every time I use the enter key the last application that I was using opens up.
I tried everything. Did a restore for a month ago. Ran all my spyware and virus software.
Looked to see if any of the software had a shortcut applied.
Went to msconfig and looked at the startup tab.
But nothing is helping.
Any ideas or help I would welcome!
I plugged in a new keyboard and it still happens so I know its not a hardware issue.
Also the enter key by the numeric keyboard works without opening the last application, but it toggles the cap lock every time I use it.
Anyone have any suggestions?
Thanks

 

Would a remap of the keyboard help to the origional settings, and if how can someone help me on how to do it.
thanks

 

http://www.usnetizen.com/fix_capslock.html

 

That program wont let me change the ENTER key.