Wow, I'm stumped now. (This is a first.

)
I hate Windows ME with a passion, my guess is it has tried to "fix" your system by restoring older versions of some files.
Barring that, I'd suspect a virus or something like a bad stick of ram, video card, or hard drive errors. *Something* in your system is bad... Does scandisk reveal any errors? (Run the complete scan, it will take a couple hours on a big hard drive.)
Of course this all could just be due to that wonderful piece of software known as Windows ME.
