Go Elite. It's about $50 more and as more and more DLC becomes available, I think the 100 extra gigs of HD is worth it. Also, it is a pretty good media player. If you ever need more than the 20gigs you get with the Pro, you'll have to buy the 120 gig HD for $180. If you get the Elite, you pay $50 for it.
Also, I believe the number of RRoDs has decreased significantly since the release of the Elite. There is a report from an anonymous Microsoft insider that says that the RRoDs were caused by the GPU becoming unseated from the circuit board due to warpage from heat, and that they've fixed the problem in the 360s with the new chips, but obviously, that's not an official line. If you do get RRoD, their warranty process is fairly streamlined and time-tested by now. There are plenty of horror stories, but then again, they're not proportionally represented against the smooth experiences people have had.
My friend and I both bought Elites in the month of July 2007, and have not had any problems with them under heavy use. Just make sure you give it plenty of breathing room.
Also, be aware that you'll need to budget for an extra controller (most likely), a big pack of AAs or a rechargable pack, a gold Live membership, and most importantly, GAMEZZZZ.
TIP: You can check the date of manufacture of a particular Xbox in the store by lifting the little flap on the top of the box. You want one made in Fall 2007 or later.