Slow to stary playing video

[Maltelec]

After reinstalling Windows and all the other programs, codecs etc, when I play my old video's it takes about 5 seconds for it to start to play them when they used to start instantly. They arn't using any funny codecs or anything, just the standard AVI Decompressor and Windows Media Audio Decoder (according to GSpot).

Its not on all video's, and not specific to AVI's