Well, I don't really like new years resolutions, because well, they're called resolutions and too many folks don't stick to them. Resolution begins with RESOLUTE; firmly resolved, immutable.
As for the actual "gut" loss, start simple. If you're being honest and you're out of shape, start with the basics, ie walking. Lots of running etc... early on will kill your knees if you've got a lot of extra weight(personal experience in this department:icon_neutral

.
After a couple of weeks of regular say hour long walking, start throwing in some BASIC weight training, not hardcore, just start light and work your way back up. You'll know when to step things up, things that were harder, are now manageable(notice I didn't say easy

). As things progress you'll find that the walking wont be enough and you'll have to start jogging short distances, and eventually longer. If you can get your weight down to a manageable level and your joints aren't shot you could start looking into something like a
Crossfit type of routine and then you'll really start cutting it up. But don't start something like Crossfit unless you're already at a manageable level(like 20-30 lbs overweight), your knees etc... are ok, and you have regular checkups with your doc.
That said...I'm on board for dropping 20 lbs:redface:. At 6'1 and 212-215 lbs(I flip flop), I clearly need to get my butt back in gear again, but I can't really run much anymore since my knees are pretty well shot, so I'm going to have to stick with day hiking and weight lifting. I may start back into something like crossfit once spring rolls back around.