Almost no programs are working- All I get is an Open With box.

[Lima]

This just started a short while ago, after I was attempting to correct an iexplorer.exe process at startup problem. Now, no programs work at all- luckily Internet Explorer still does.

When I say no programs, I mean nothing- AIM, games, System Restore, regedit, nothing at all. Everything I try to open, the Open With... box comes up, and I have no idea what file all of these programs need to open. Even the cmd prompt will not open- I get the same Open With... Choose the Program You Would Like to Open With dialogue...

I would like to correct this problem without reformating (I can't backup my files since cd burning programs won't open, either). If no one can diagnose what file may have been deleted / changed to cause this program, my second question is what do I need to choose in the Open With box in order to run System Restore, etc.?

Thanks.