Is the area in and around the Iceland Airport worth checking out? i.e. the Hotels or restaurants near the Bay?? Reykjavik just seems like a bit of a drive for a one day layover...am I wrong? (And there must be buses that can transport you from the airport to the 'blue lagoon' and back...?)
Keflavik airport is very close to Reykjavik so getting there is not a problem.
However, if you are wanting to see a bit of Iceland's magical landscape, I would actually suggest that you arrange an airport pick up and do a day tour in the stunning countryside (I would highly suggest some lava caving).
You can easily arrange this with any of the private tour companies but, if you need a bit more of direction, I would contact the tourism office http://www.visiticeland.com/ as they are very honest and very helpful.
They are always my first resource when visiting Iceland!
PS -- the Blue Lagoon is actually a very popular stop on the way to/from the airport. The facilities on site are awesome so, if you just want to relax a bit on your stopover, this is def a good option. Just depends on how long you can take soaking in the thermal pool :)
There's definitely a regularly scheduled bus. It's called the FlyBus, and it's a 45-minute ride. Here's a blog post with all sorts of info about my first day there.
My best idea for you: Stay longer. Iceland rocks.
I am pretty sure that one of the bus tour companies collects you from the airport and can take you straight to the Blue Lagoon. I can't recall which one but am sure it would be on the website. There is also the Great Circle tour out to Gulfoss Waterfall but that might take longer. Iceland is cool. We did a 2 day layover in May 2012 and it was loads of fun. Enjoy!
There's not much to Keflavik, where the airport is. It's definitely worth the drive to get into Reykjavik for a one-day layover. It's such a cool city ... you won't regret it.