Recorded mpeg playback problems

I have a WinTV 150 card and have been recording television shows under a number of different formats (DVD Standard Play, DVD Long Play, MPEG2, etc.). The programs seem to record ok (I’m using WinTV Scheduler to record 1 hour long programs), but I’m having problems when I try to playback any file.

I’ve tried both Windows Media Player and Real Player to play back the files with the same results. I get a scroll in the message bar “Connecting..." and then the file slowly starts to play and then altogether hangs up after a bit.

Any suggestions for what I may be doing wrong or what I can do to get this to work?

Thanks so much.

P.S.
The 1 hour program file sizes created are between 1GB to 2.5GB depending on the format.