I may as well have a flat there.
Yep, need any info and we'll help out.
As said only problem where you are staying is having to metro it in (or a nice walk via the beaches and Barceloneta) and depending on if the metro has finished later. Saturday nights and night of holidays usually means the metro doesn't stop running which is good.
Buy a T-10 as well, as its under ten euro for a ten trip pass that can be used on buses, metro, trains etc within zone 1 (covers the airport BUT not the airport metro - there is a half hourly train from Terminal 2 which stops at Sants and Passeig de Gracia stations in the centre). Transport system is pretty good. Taxi wise, if the address for hotel isn't on keycard etc just ask hotel for an address card, then if any language issues just show the driver the card.