MPEG Issues. Options

[Redd]

Aight, so I'm having horrible issues with MPEG. I'm trying to make a movie right now (WMM, very basic), but it won't let me import MPEG. And the sad part is that it used to, but now it randomly doesn't. It doesn't even give me a good error, it just says "awefawefasdfasdf.mpeg could not be imported" and that's it. I've tried installing K-Lite codecs and Shark007 codecs (virus scanned of course) and neither of those are working either.
I'm using 64 bit Windows Vista. But this is really weird because the family laptop, which is 32 bit Vista, lets us import MPEG just fine.
The camera I'm using is a Sony Handycam if that helps at all.
I've looked around the internet and nothing is helping, so I figured, you know... people here are smart

If you could help me, that'd be SO FANTASTIC