Batch change video resolution?

A few years back I ripped all my Red Dwarf DVDs to iTunes but they're a few pixels over the iPod requirements. Is there an app or script that automatically goes through each vid and shrinks them down, I thought about converting to iPod within iTunes itself but that renders the video again and I don't want to lose quality.

Is there an easy way to do this?

(I asked this years ago but I'm hopeful theres an automatic method now)