Premiere actually crashes a lot on me. =\ (I run an i7 computer)
Also, After Effects may not be what the OP is looking for. The programs he listed are editors, while AE is geared more towards motion graphics
Depends on what you want to do. I don't know much of the effects side of Final Cut (I use a PC), but depending on your goals, AE may be easier and better. If your goal is to stitch together video clips, 90% of projects can be taken care of with iMovie or Windows Movie Maker (respectively). The only reason to get a big fancy program is for the ability to layer multiple tracks and have fancy effects capabilities. Without knowing what it's being used for, its difficult to say which (of any) is best.
Being that this is a photo forum, I can think of at least one use: video slide show. If that's the case, the best and easiest option is Animoto (google it). If one so desires to make their own, AE would be a lot more suited.