The iMac would be perfect for your needs. Some say the MacPro is better, but most people would never push an iMac to the degree that they feel a need to ugprade.
Having used the new iMac today, for an extended period, I can really recommend it as a great machine, the build quality, performance and design is absolutely fantastic, unlike any other machine I've seen.
It seems almost like more of a pro machine when you look at the performance and build quality/design. Like a MacPro, in one box.