I am wanting to buy a 24" imac (one snow leopard is standard) but I am unsure which one to get. I mainly would use it for word processing, watching movies, itunes, surfing the net etc. I was thinking of getting the 2.9 to "future proof" myself, but knowing me I would want a newer model down the track. Would the 2.66 suit my needs? I really want it to be zippy