My movies are all screwed up now? HELP!!!!!

[Rickster]

I've reinstalled Win98SE and then DiVX then SMR codec and now when I record my movies (PC to VCR) or just viewing them on my PC, most of the time they are fine but since I reinstalled, the movie is playing then all of a sudden it goes like in fast forward mode?? I use My ATI file player or PowerDVD, My PC is AMD TB Athlon 1.33 GHz 30GB HDD with 256 SDRAM (PC133) would anyone know what could cause this and how I can fix it? thanks