Futurama: Screen Grabs?

Hey all!
Didn't know where else to go for help, and I figured that you guys might be able to help me.

I have to make a flash animation for my Digital Imaging class in school, and we were able to choose any theme we wanted for it. I chose Futurama, bur I've run in to a little bit of trouble...

I need a picture of the interior of Planet Express (preferably with either no one in it or with the main characters sitting around the conference table) or of the Planet Express Ship (again, preferably with no one or just the main characters). I need a fairly high resolution pic, but my computer forbids me to take a screen grab when playing in iDVD. I've searched google high and low for anything, but nothing like what I need has shown up, and CGEF is great but the pics aren't a high enough resolution.

If you could either tell me how to take a screen grab (I have a Mac) in a way that will allow my computer to do it, without taking up too much time that would be amazing, and if you found one for me I would be forever if your debt...
Thanks in advance
Alex