Which is best hotel that is in the historic district. Would like one that has a nice breakfast,

Hampton Inn Andaz The Brice Marshall House

Any other suggestions?

The Andaz is great for breakfast. More than just "nice." There are several threads here, including one current one, that discuss this very question. I liked the Andaz a lot when I stayed there a few nights last year.

Having stayed in half a dozen historic district Savannah hotels, Andaz has become my favorite -- having now stayed there twice.

Don't stay at the Olde Savannah Inn. Just take my word for it.

Since my husband can't walk long distances, is the hotel close to getting a pedicab or taking a hop on hop off bus or trolley? How is the location for a short stroll?

The Andaz puts you right at City Market and 1 block off of Broughton Street, so lots of shopping and restaurants within easy walking distance. The Marshall House is on the other end of Broughton Street, so you'll also be able to walk to many places. I'm sure that you can check the map of the hop on-hop off bus on the website for Chatham Area Transit (CAT), which operates it. You can get pedicabs just about anywhere, but there would definitely be a lot of them at City Market and the hotel could also help you obtain transportation.

I'm sure that the Hampton Inn is nice, but it's location is at the other end of the Historic District; not as many places within easy walking distance.
Hope this helps & hope you enjoy Savannah!

Well, based on your advice, I just booked a room at the Andaz for our upcoming weekend in Savannah. Thanks Fodorites!

I hope you are registered for Hyatt points. There are so many benefits to that program. If not, do so immediately.