I would use the Apple online store, although if you're somewhat tech savvy, don't buy RAM from them. You'll probably want to up the hard drive size from the default, with all that stuff.

As far as the iLife stuff goes, it's all pretty good from what I hear. I only use iPhoto and iTunes, but those work well. It depends on how heavy a video editing load you're going for. I'd say give iMovie a shot for now; if it's not enough, get Final Cut Express later.

I am the Doctor, and THIS... is my SPOON!