Late Nov. is a good time to go - public spots shouldn't be too crowded, at least mid-week.
If you're only going to have 1 dog for a 2 week hunt, make sure he's very fit before you go, and limit the number of hours per day for the first few days until you see what he can handle. Also try to limit the amount of time in the real heavy cover as it really beats the dog up as the days go on. I keep my dog pretty thin, but if I were going to try to hunt him every day for 2 weeks I'd probably start out with a touch more flesh on his ribs than usual - mine at least generally can't eat enough to keep up if they're hunting all day every day.
If it were my first time out there and I had 1 dog and 2 weeks, I'd probably not stay put in one area but would cover a lot of ground, maybe even hunting both N and S Dakota and spending a few days in western N Dakota chasing huns and sharptails - that way you can see a bunch of nice countryside, hunt the choice looking spots you come across, and not beat the dog up too much.
