Vista - PHP file associated as "web" Please Help!!

I was using a mac keyboard on my PC (big mistake) and was trying to italicized something when somehow, I pressed something else which caused my PHP extension not to open properly in firefox or IE8.

Here's what happens:

I double click the php file on my deskop (it only contains HTML, btw) and instead of displaying the page, BOTH IE and Firefox prompt me to download or open the file.

In other words, they both treat it as an application. I've tried changing the filetype with creative power tools, but that didnt work. I also tried a system restore to a day before, and that did not work.

I know the php files themselves are fine, because I opened them on another pc and it displayed fine. So something I imagine in the registry is telling firefox and IE8 that any PHP extensions are applications or unknowns...

What can I do to fix this?

Thanks so much!