Capturing/Burning Advise Needed

[Pat Sullivan]

I am wanting to transfer some of my kids Disney tapes to DVD so they 
will quit getting eaten in the VCR (fair-use in my book). I am using a 
Sony TRV120 as a bridge. So far I have made some VCDs with Toast and 
SVCDs with FFmpegX and VCD Builder, but haven't tried DVDs yet. I just 
got iDVD and haven't started to learn it yet. Using a Sawtooth, Dual 
500, 256 RAM, IBM Deskstar 120, Radeon.

My questions are:

I have BTV Pro, FCE, and iMovie. Is there any difference in how these 
programs capture the video? So far I have used BTV Pro and the video 
seems very slightly jerky during fast motion. Is this an artifact of 
the DV compression or?

For those films over 90 min, how is the DVD best recorded? Can iDVD be 
hacked to record longer than 90 min, or is there another program that 
can be used? (Please suggest something other than DVD Studio Pro - I 
don't have that kind of money)

What is the differences in encoding between iDVD and FFmpegX? What bit 
rate does iDVD encode at? How fast are these two in comparison to each 
other?