I don't know Pinnacle very well, which version are you using?
If the error is with the rendering, it might well be something on the timeline that's causing problems, are there any very complex effects or transitions?
perhaps you don't have enough space on your Hard drive?
or it may be partitioned in the wrong way, if so... (from a post by Mihai)
If you post more details or do a search for your problem you might find something usefull.
... the partition you use for video capture is formatted in FAT, which has a 4 GB file size limit. Convert it to NTFS.
You can use lot's of different software to encode to MPEG2, so you don't have to buy it from Pinnacle.
I think all Mac's have a firewire port as standard, so you could use that to transfer I'd imagine. I'd just connect the two and see what happens.
If nothing happens, you could always get Pinnacle to "Export to Tape", which will play the file out through the firewire port, then use your capturing software on your Mac (imovie??) to captur it. You might need a different firwire cable.
Sorry if I've confused you further , and good luck.
Panasonic SD9, Panasonic NVGS-75, Canon MV600i