If I record in frame movie mode on the GL2, in 16x9 or 4x3, can I use an older, simpler miniDV camcorder (canon zr-60) to fransfer via firewire to my computer? Will a camcorder that doesn't have 30fps frame movie mode playback and transfer video shot on the GL2 in frame movie mode?

Yes, there's no problem with that. The playback camcorder or VTR doesn't care if it's Frame mode or not.

Chris is right - it's simply a digital file that's being transferred - some millions of ones and zeros.