Dental implant. In general, a dental implant is the best way to replace missing teeth. The next best option is a fixed bridge, followed by a removable partial denture. Much of this depends on your individual situation with the surrounding teeth, bones and gum tissues.
It depends... I would see your dentist who can make the better determination. If much gum tissue is missing due to bone loss and recession, then a partial may be more esthetic. Generally a fixed bridge is a better option. However, I would see your dentist to help with what is best for your situation.
Fixed. Fixed units are almost always better because they tend to be stronger, more esthetic and you can't lose them so easily. Down side really is just cleaning it. Removable is less expesive normally but can be broken or lost and is more difficult to look as good. Just so you know, an implant is superior to both though.
Fised bridge. If your teeth are strong enough to support a fixed bridge, all the evidence in the literature says people prefer a fixed bridge over a removable prosthesis.