longer boards are better for crusing, but dont carve so well, so be sure to get one on the shorter side. you want trucks that will turn like they are really loose (on other sketeboards) but will at the same time be stable(no death wobble or board flipage, etc.) i have a sector 9 with those carving double trucks(cant remember what they are cald) but they seem to work well for me.(see note) Origional Longboards has some ones that look like they work well, but i haven't tried any.
note: i live at the beach so i am in lack of really big hills, but i've managed to find some