Editing video from my SD870IS

I would like to be able to do simple video editing on clips from my SD870IS (crop, adjust start and end points... to adjust volume would be a bonus). I have a version of Premiere Pro.

When I edit the video on my camera—basically just cropping the video file, I get great results and small file sizes. However, when I try to do the same thing using Premiere, the output file size explodes to about 10-20x the original!

I believe that I am choosing my export settings to be far higher definition than the original file... like using ultra-high defnition audio recording equipment to record an AM radio broadcast. I figure that I just need to find the optimal export settings which are appropriately matched to the original recording parameters.

What settings (frame rate, etc.), codec, file format and codec settings should I be using to open, edit, and save the file without making the file size balloon up? I'm shooting in 640x480 and 640x480 LP.

Screenshots, examples, tutorials, or any other kind of walk-through would be much appreciated!

Thanks

Where do you ultimately want the file to end up? DVD? Web?

And what export settings have you tried using?

If you just want the file to be used on the web, I would recommend using the h.264 codec. Keep it the same size since shrinking the size of the frame won't reduce your video file size by any significant amount. Set the keyframes to Automatic and adjust the quality slider until you get the size you want. I find h.264 the best balance between quality/file size.