In the last week or so when I watch videos (DVDs or on my hard drive but less so when I am streaming) I find that very often the video freezes but the audio keeps playing. Then anything from 3-10 seconds later the video will return and play very fast to catch back up with the audio. it is very frustrating and I have no idea what it could be. I can't think of any major changes on my PC that would have caused it to start happening. It could be the graphics card or the CPU, don't know. Graphics drivers are up to date. Any one got any ideas? Cheers!
Codecs Have you installed the latest codecs http://www.free-codecs.com/XP_Codec_Pack_download.htm this may help
Installed anything that runs in the background? Might be worth checking your processes for anything that shouldn't be there. If I had to guess I'd say somethings swallowing all your cpu power at intervals. Wouldn't expect it to be a hardware problem, though at a push it might be something overheating.