In PnP, you don't have quickslots. :p
My sorcerer doesn't have any metamagic feats, so I've not really tested it, but I'm kind of thinking you have to quickslot metamagic spells when your a sorcerer since they metamagic spells don't show up in your dial display (Kalin or Alantha could chime in here). That is, quickslot from your list of known spells (by pressing "b" on your keyboard). And like Dorg said, in NWN, metamagc spells take the same amount of time to cast whether a wizard or sorc casts them, so no, not a full round.