Well, let's see!
The most common male names are "Antonio" (702,882), "José" (625,280), "Manuel" (609,506), "Francisco" (519,796) and "David" (361,991). Compound names are counted separately, with "José Antonio" coming in on 7th with 314,363. "Alberto" is no. 27 with 180,009. For female names, "María del Carmen" is surprisingly the most popular (664,804), followed by plain old "María" (624,184), "Carmen" (407,389), "Josefa" (290,950) and "Ana María" (275,622). Except for "David", the average age of all these names is fairly high - these are very traditional names and plenty of young people would bear them, but newer generations tend to like variety a lot more.
As for "old-fashioned", that's harder to say. Looking at the most popular names for people born before 1930, most of them are still common and sound fine. The real gems are obscure religious and saint names, none of which was ever particularly popular on its own, but which, taken together, made up a significant portion of the total. Like "Anacleto" (510 people/average age 67,2), "Remigia" (309/71,5), "Fortunato" (1231/69,2) or "Tiburcia" (161/77,5). Unfortunately for me, many totally awesome Germanic names are in this category and I consider them unsusable xD.
I'm getting all this info from Spain's
Instituto Nacional de Estadística.
Here's a widget to play with, and
here's the additional data.
Oh, and apparently, of those 5398 guys called "Luca", 1438 are actually Italian.
edit: Partially ninja'd *shakes fist*