iMovie is a great way to learn the processes involved in getting video from tape to your machine.
As Cassiachette says Final Cut is definitely the app to get for the long run but that doesn't mean you should stop using iMovie either.
iMovie was designed for the rough cut edit and it is the perfect tool for that more so than Final Cut as Final Cut is designed for more intensive editing (we're talking frame by frame edits, layering, and special effects here).
Get the video into iMovie, remove the stuff you don't want, keep the stuff you do want, and then export to Final Cut (remember to flatten the audio otherwise audio isn't transported into Final Cut) and then make your final cut (not called that for no reason

).
Final Cut Express is a great animation tool as well. I've done some stop go animation using nothing but a still camera and Final Cut Express. The fact you can edit frame by frame is so handy.
Have fun and don't forget we can help out where we can.