[nostatic]

$2600 will get you a Moots YBBeat softail Ti frame. There is no reason to spend more than that. And if you want a hardtail, you should seriously consider going with a small steel builder. that should be $1K-1.5K for the frame. As for the build kit, I've been out of the loop for awhile but the conventonal wisdom is that Shimano Deore LX is great bang for the buck, XT saves a bit of weight and has more status. As for discs, I think it depends where you ride. Here in SoCal where it is usually dry, I don't see the need. A V-brake is wonderfully simple and stops great. If you ride in a lot of muck I think disc brakes give an advantage, but you have to ask yourself if you really will ride in those conditions.

The biggest variable is whether stock geometry will work of if you need custom, and what fork you want to run. I can't help you at all on that front, as I'm switching from a very old Judy with Englund air cartridges to a rigid front fork on my Moots. I'm going old school...I'd go single speed as well but my knees and hips would never tolerate it.