I'm surprised I didn't post this over a year ago.
I can't recommend enough FastStone Image Viewer
I don't use this to edit my RAWs, rather I use it for a quick pass on a dump of RAW from a shoot and preview and delete the ones I don't need. I do some batch re-naming and resizing with it from time-to-time, but mainly for just proofing my RAWs. But if you are in a bind or need something that's free, then try this one out.