Jeez. . .you could have done a lot worse. I have a 9'0 Hydro Hull in the quiver and it's a great, great longboard. It will hurt you if you are not careful, though. It's a lot of board. I wouldn't take it out on waves that are sucking, barreling until you know what you are doing. Look for mush-ball waves.
Just set the middle fin in the middle of the box. You generally move it forward in the box if you want to make the board super easy to turn. If you are just learning, you aren't going to notice much of a difference, anyway. It's a fast as hell board once you get it pointed in the right direction.
If you want a second board, I'd recommend a fun shape in the 6'8"-7'6" range. Something like a McTavish Carver. Foam is your friend until you know what you are doing. The earlier you can get into a wave and onto your feet, the better off you'll be. This advice is applicable to 2' waves and 20' waves.