Why solid hardwood is the best choice
If I've talked you out of installing the floor yourself, you may want to try prefinished-hardwood flooring. Some of it can be easy to work with, but follow all the instructions with respect to acclimating it to the room.
Floating-hardwood flooring, which is not nailed to the floor below, is also gaining in popularity. The pieces interlock with one another. Sometimes the connection is mechanical and other times it's a glue joint. These systems can be challenging to install if you've never done it before.
You'll love solid hardwood flooring if you decide to use it. It's the only material I'd use in my home. I love everything about it. Perhaps the best part is knowing that it can last hundreds of years. If you care for the finish, it only needs to be sanded lightly when it's installed. Every coat of finish after that only requires a light screening of the previous finish. There's no need to sand the wood.