Choppy video in iMovie/iDVD from Sony HDD Camcorder

Question

I feel like I must be doing something wrong here, I've just moved from a windows XP machine to a nive shiny iMac which is lovely and I just want to hug it a lot, but.....
My DVD's just aren't coming out right, here's me thinking Macs were renowned for their video editing, but all my stuff is looking better from windows.
To explain further, I connect my Sony DCR-SR32 to the mac via USB (the Sony is a hard disk camera which records to mpeg2) iMovie recognises the camcorder and allows me to import all my clips. I spend hours putting together some holiday footage with appropriate fades, titles and cuts. I then import the finished project into iDVD and spend more hours messing with the motion video menus and getting everything looking right.
I then burn to a DVD and it looks horrible, the frame rate looks like it's about 10 fps and it's jumping around all over. After some research, I find that Perion is probably to blame, and I can work around it by exporting from iMovie as a DV file or removing Perion which I've creating a DVD.
So the output is better, not so jerky, but something is not quite right, while it's not jerky its not quite as smooth as if should be, and the colours seem to be a little more pixelated a bit like when a divX movie struggles in an area of low contrast.
I'm comparing this to running XP in a parallels session, attaching the camcorder and hitting the "Disc burn" button which burns a lovely smooth and colourful DVD without a problem.
I thought this must be an issue with the conversion, convert to h.264 when the file is pulled off the camcorder, and then again into mpeg to burn must be missing something, but I took the raw mpeg files and got Toast to burn a DVD and that was the same "not quite right" result. I've read a lot about OSX's difficulties with mpeg2 and suggestions to use Streamclip with the MPEG quicktime plugin - will this do anything better, it just seems that with any conversion you're going to lose some quality, and converting several times to get something into iMovie then again when iDVD prepares the disk seems to be asking for more trouble ?
I've double checked all the obvious things, like is it set to PAL, and is the DVD burning at the best quality. I'm even burning to disk images to take the physical DVD out of the equation.
But still the results are not satisfactory. I really don't want to have to run windows still, iMovie and iDVD - although fairly basic were really nice to use, and the overall result is great... if I could just get it to look right.
Any idea on what might be wrong in all this, or how I can get a better quality movie to burn ?

Answer 1

Ok, this time I tested it in playback mode.
Connected USB. Chose HDD connect. NO NAME appeared on desktop. Opened iMovie (started my stopwatch at this point). Detected camera - scanning. Generating thumbnails (at this stage it is generating thumbnails for all the clips I have on my camera. For the record, I have 6 clips of 52secs, 22secs, 40secs, 27secs, 29secs and 1min). Finally, after around 1m50s, the 'Import From' window pops up showing me the thumbnails for each clip. I stop the stopwatch.
I only want to import the 1min clip this time, just for timing reference. To import this 1min clip on my imac (see my mac profile below) took 2m30s. This includes generating the thumbnails too, although I'm not quite sure why it does this again. I think 2m30s is very slow considering that DV would/should import in real time.
Anyway, those are my findings today and I for one now have a better understanding of how to connect my camera...playback mode only!
Thanks.
Lee