I just came back from Ao Nang.
Krabi town is shit. Don't bother staying of visiting there. Period.
Ao Nang seems good to me.
Nice beach. We stayed at Holiday Inn which is if you can imagine to the right hand side of the main drag...
It's about 10 minute walk to the 1 main road.
Loads of restaurants and a small bar area.
You can get tours sorted to the islands from all the hotels easy.
Bear in mind, James Bond island involves an hours drive to another jetty before you start.
Great place. 3 nights max for me. Make sure it doesn't rain or you will be jumping condo.