I have a a 2009 rockhopper disc and was wondering what upgrades I can get for this bike, or if it's worth getting a full suspension bike?
One thing i know i need to get is a set of clipless pedals and cleats.
any suggestions would be great, thanks!
You should definitely get some cycling shoes and clipless pedals - First. Even the bottom of the barrel ones will help your riding immensely. That said, Shimano pedals are indestructable, but wont clear mud well. Crank Brothers shed mud better than anything, are super light, and are really easy to use. Time pedals are right in the middle and are my personal favorite. Shoes - go with what is most comfortable up top - try to get something with a stiff sole, keeping in mind that they wont be comfortable when walking around trying them on.
Once you have shoes and pedals, your first and best upgrade should be the wheels. If you're prepared financially to even think about a FS bike (which I think you dont need, BTW) you can afford to spend a few hundred bucks (+) on a really nice wheelset. Keep in mind that in the future, when (not if) you buy a new bike, you can use the wheels on your new bike.
After wheels, if you're set on upgrading rather than buying another bike, your fork is probably heavy and there are certainly better options out there.
Drivetrain upgrades are generally overrated. I'm assuming that you have half decent stuff on there already, and its probably bomb proof. Eventually, you'll break something and that's a good opportunity to upgrade it. You'll need to replace chainrings, cassettes and chains as routine maintenance anyway.