Need help with a San Francisco trip

[trying2learn]

My wife really wants to go to San Francisco, and while I can't think of a worse time of year to go then late December...that's when we have time and the flights were cheap.

My question is this - as far as nice, upscale hotels go...what does OOT reccommend? I've heard Renaissance Parc 55 is the best...and after googling I have about 5 others that look good...but I figured I'd ask the best for your opinions too.