No, I think you have to reinstall.
Make sure you download all file secure, this problems happend when you install the program in some way that is not the right one. And one advice, download Photoshop CS2, it's better cause have a simple design and the same tools of CS3!
I guess it really did fail catastrophically. Oh well, Thanks anyway =)
Edit: Didnt notice Bueenos post. Sorry =(
I would but I can only find a DL for photoshop in Imsoonobz tut.
Ill keep my eyes peeled for a CS2 then. =)