L'Osteria has pretty good European-style pizza at great prices, considering the sizes. They happily split a single pizza between two guests and let you order half-this and half-that. Monday through Saturday, they open at 11:00 according to their website at http://www.losteria.info.
Note: it can get really, really loud in there, due to the acoustics and sheer number of guests. Best to go at off-peak hours.