If my SR Suntour P.O.S can run disks, I'm sure the darts can.
P.S The dart 3's aren't that mush more expensive, and it's still better than the stock crap.
Dont they make a disk brake adapter thing?
My frame doesnt have disk mounts, but its got a few holes above the derailer mounts.
EDIT:
http://www.pricepoint.com/detail/15674-315_ROCD27-3-Parts-59-Forks/Accessories/Rockshox-Dart-2-80mm-Suspension-Fork-'07.htm The dart 2 is 80.00 right now and is both disk and V brake compatible. The V brake bosses are removable if you decide to go disk.
But if you go disk brake route, you'll also need a new hub for your rim.