I just purchased a Sony HD Handycam (new 2010 model) and love it so far. I do not have a blu-ray player (let alone a blu-ray burner) so my primary interest is making 16x9 SD dvds of movies I record that still look pretty darn good. I have a MacBook Pro with iMovie '08 on it. (No I don't have Final Cut :-)

So.. here are some questions...

1) Since in the end all I want is to make a standard dvd of my recordings, I assume it's better to record in HD and then downconvert than to record in SD right?
2) iMovie is able to import the .mts files from my camcorder and when doing so, it converts them to quicktime files. I have no idea what specs iMovie uses. Can I trust them? If not, is it better to convert the .mts files with some kind of converter program instead of using iMovie? I've seen free ones on the net that are made for Mac.
3) When I export a project from iMovie (so I can send it to iDVD to burn), should I just "share it" by making a "large" file that iMovie puts out or should I export to Quicktime? (I actually tried doing this, the "large" file that iMovie exported was about 500 megs (for a 20 min movie) but when I exported in 720 HD to Quickime it was 4.5 gigs!!

I guess I'm just trying to get the best picture possible in SD without having to sacrifice a ton of hard drive space.

Any thoughts you have would be great! Thank you