Hi folks,
I've had alot of experience with TIVO and Replay 4000 files, and I think if you are using an older Replay one of the problems might be the MPEG file it self. While playing it straight after taking it off of the replay is not a problem, it is usually one of two things.
The GOP Structure, and the time coding.
There are two programs you want, well really there are a dozen programs you need to properly do this, or at least a half dozen if all your doing is taking programs from Replay and putting them on DVD.
The two most important for "fixing" replay mpegs are, PVAStrumento
and Timefix.exe
One program can be found at
http://www.offeryn.com/
this guy is awesome, the program is screaming fast, and actually does what it says it will. It goes through an MPEG2 file from a PVR, TIVO/Replay/PC based, and will fix the structure so that programs expecting a more standardized format will be able to deal with it.
I believe if you search Timefix.exe on this forum you should be able to find it. Let me know if you can't and I can post a link to it.
Basically I use Womble, with UleadDVD to make DVD's of the shows I put on Replay.
Hope this helps.
TimT