Any of the ones you listed are good cameras will do a good job.
The HDR-H3 would future proof since it's HD.
The iMac is fine it's has firewire. Do you have iLife 6, this will handel HD in iMovie.
You will need lots of hard drive space also. John
i am trying to decide what camcorder to get..i have decided that i at least want a miniDV. but cant decide btw sony hc 96, panasonic gs300 or go higher end with the sony hdr-h3. i have a imac computer. if that makes a difference...

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