Not enough information. Some people put so much nonsense on their beef that it barely resembles what it actually is, so if you tell me you're going to have a parmesan-encrusted roast beef you'll have an entirely different recommendation than if it were not.
That said, I couldn't see myself drinking anything other than a big red. A Merlot, imo, won't do; I think I'd have to go with a Syrah, or at least a blend that has Syrah character. With that in mind, I'd likely choose a Chateauneuf du Pape just because I can, and for that I'd likely seek out a Vieux Telegraphe or a Beaucastel as they are largely consistent and accessible. I have some '03 Clos Des Papes that I'm saving, but prices have skyrocketed for those bottles. '03 was a great year, but not drinkable yet for the better wines.
If you do inundate the beef with spice rubs or anything else, then I'd go for something a little softer. I'd probably go with a Barbaresco simply because I favor them, but a nice Merlot would work well. If I were to go Merlot, it would have to be a St. Emilion Grand Cru Classe or a Cali Merlot.