You could try some of the gastropubs such as the Rosendale and West Dulwich and the Windmill in Clapham. There is also a B and B in Lee which gets a lot of recommendation. Apart from that I agree there isnt a great deal around here. There are a few hotels in Greenwich and Docklands is the Hilton in Rotherhithe.
There are also some in Bromley and Crystal Palace but many take DSS so I wouldnt recommend them.