Try importing into iMovie? (Open iMovie, plug in cam, it should see it.) I doubt however that your monitor will display it at HD resolution, but correct me if I'm wrong.
Weird. Maybe try converting them with iSquint or something? Even try changing the file ending to .mp4 or something; sometimes that works. Alternatively, download extra plugins for QuickTime, initially my friend's MBP wouldn't play a .mov file, but then we went here and got DivX and Xvid, which did the trick. CheersiMovie doesn't allow me to select it when I try to import it. Unfortunately, I don't have the camera with me anymore. We shot it at school and all I have now are files on a dvd
FCE? Too bad there's no demo/ trial. If the videos work through it though, it might be worth the upgrade, less pricey than FCP but still very good and significantly better than iMovie. Still, give those extra codecs a try first.
Oh.
Some codecs only come w/FCP (such as ProRes). HDV may or may not be in the same boat since both iMovie and FCE do not work w/HDV natively (they transcode it into AIC).