Lots of people recommend a shotgun for home defense, but they never talk about the need to train with one. The shotgun can be a great home defense tool, but it does require training and proper ammunition. Do not, I repeat do not use bird shot. Use 00 buck in whatever load patterns well for you and make sure it keeps all pellets in an 8' circle at 15 yards. Shotguns do not usually spread way out at short ranges like in the movies, and yes you must aim them. Watch the Magpul dynamic shotgun dvd's if you want to get a good education on the shotgun in a defensive role.
As far as handgun goes, I have something on my nightstand that is almost exactly what you are looking for. It's a CZ SP-01 in 9mm. It's full size, has a rail, night sights, safety and a 19 round capacity for less than $600. It's a fantastic weapon and CZ makes excellent products. I also have a TLR-1 light mounted on it and I really think the light is great for a home defense gun. It's worth the extra $100 for the light.
You said you were going to get some training, and that is a great idea, join IDPA and shoot some matches, they are great for learning to handle a weapon in lots of scenarios and they make you train reloading, using cover etc... Watch the Magpul dynamic handgun dvd's as well, they are great and even cover concealed carry and gear choices.