You should stay at the Melia, which is a fine hotel, if the rates are right. There's a few other good, classy hotels up there, but not a lot. We were in an apartment-hotel bldg near there, and the neighborhood didn't please me at all. The Melia, though, is right on the Castellana, which is fine. You can then take a bus or metro right down the Castellana to get into the more central downtown area. Also right near there is the Eurobuilding, which is a fine hotel too.