I quit wow a while back and have experience with rogue, druid, and priest both in high rated arena, bgs, and pve. I plan to come back in Cata and I want to try a new class. I'm stuck between warlock and DK I have no experience with either class and I hope to arena, bg, and pve which class is more fun, easier, better choice and shows more promise in cata?
Also I go to school and work a lot I feel that I might only have a little bit of time to play wow as in find a guild that raids 3 nights a week for 3 hours a night and maybe I would have 3 hours or so for the rest of the week to do bgs and arena.. would this effect my ability to really have fun in the game by being so casual? ( as far as gearing on my own, getting gold.. so on and so on)
Since you plan to come back with Cata, we can't answer your question, because by that time, classes will change quite a bit: both warlocks and DKs. And at this time, there really isn't enough information available to tell which has more promise of being fun.
However, I can answer your second question: yes, you can have fun no matter how casual you are. You just need to set a goal you can achieve, and shouldn't try to force yourself to do more than you have time for. Then you'll have fun.
13.6.2. Pointless threads
"Which class should I roll?" is a frequently reoccurring thread.
There is no real discussion to be had about which class any individual should play. This is a very personal decision and all anyone can really do is post their personal favourites over and over again.