PC utilities forum: Windows Movie Maker Crashes

Sorry- this is quite long, but I thought it might be easier if I explain a couple of things about my computer beforehand.

I am running movie maker 2.0, with Windows XP Professional. I have 512mb of ram and plenty (22gb) of free hard disk space. I have WinDVD (but not WinDVD creator), ITunes, Quicktime and Windows Media Player installed, but not IE7 (only IE6).
A couple of days ago, I stopped it from crashing on startup by deleting a file in application data (I must have imported a dodgy file) and it seemed to work fine...until I tried to import something.

Once I've browsed for a file and clicked 'ok', it pauses for a few seconds, and I get the message "Windows Movie Maker has encountered a problem and needs to close. We are sorry for the inconvenience." My only option then is to click on 'close', when it crashes.
I have tried with a number of different file types and have had the same problem (I've tried importing video, pictures and audio/music). However, I can still click on the transitions/effects links and add titles/credits without a problem.

What could cause this problem, and how should I go about fixing it?

(This may have been mentioned in the forums earlier here, but I've checked here and at WindowsMovieMakers.net, for about 15 minutes each and haven't found anything about my specific problem. I've also had a look at "Crashes/Hangs" on Papajohn.org a , but I'm not sure if it's codecs or something else that's causing this problem, so I thought I'd ask first.)