HD video capture/editing (Final Cut Express) requires which MACBook

While most of my editing can be done on a MAC Pro, I was wondering if while travelling I can get some of the HD video capture and editing out of the way on a MACBook and if so which one could I reasonably get away with if I want to keep the size and price down. The 13" MACBook with 2GHz and 2Gb RAM possibly with an external HD?

The type of stuff I do is family home movie and I am not looking for professional quality editing result by any means. Quite happy to cut out the rubbish and leave it at that but I do want 1080 HD image quality. I am inexperienced at this as you probably read into this and hoping to spend as little time behind the computer as possible - however wonderful the MAC may be... and it is of course. Thanks!