Is there any way I can mix n' match both types of clips in a single project?

That is, some DV clips from an older camera, together in the same project with footage from my HC-1 shot in 1080i/HD mode in iMovie?

I'm suspecting I cannot, but was hoping someone had a cool work-around!

Thank You,

Reilly

I am unfamiliar with iMovie - presumably you have already tried to do this. I think you either need a nle that can handle mixed formats on the timeline (such as Edius) or you transcode one of your formats to match the other. ProCoder or ProCoder Express should be able t do this for you. See here:
http://www.canopus.com/products/ProCoderSW/index.php

No doubt there are other converters around.

Check this info from Apple...it might help

http://docs.info.apple.com/article.html?artnum=300830