As someone now based down here there are a few drinking options.
As noted earlier Wind Street has a selection of bars and is the main area for nightlife. It's not for the feint hearted and is a melting pot for 16-90 year olds who are all on the lash.
For something a bit nicer I'd recommend the Riverhouse in SA1. The beer is good (Moretti) and it overlooks, as the name suggests, the Tawe River. There's lots of pay and display car parks nearby... or you could chance leaving it in Sainsbury's, which is just 2 mins walk away over the sail bridge. SA1 is only 5 mins walk from the town centre.
If you choose the Riverhouse you can also walk alongside the river all the way to the ground, which takes about 20mins.
As for hotels there's a Premier Inn and a Village Hotel in SA1. There's also another Premier Inn and a Travel Lodge in town (close to Wind Street). At the higher end there's Morgan's, Marriott and The Dragon. Out of those I'd recommend Morgan's.
Beyond that you could opt for a B&B on the seafront, but you might not live to tell the tale :-)