For long roads and fairly open mowing (as apposed to much of the time getting into tight places and backing out): your options are wide open! Not sure how hilly is hilly, so I'll start with the cheapest option, assuming no real tractor challanges of hill.
If the availability is decent in your area, and you're not entirely wrench sweamish, and older 40-50HP AG (i.e. farm) tractor may treat you well even coming in way under budget. Actually most shops around here will work on these, but they're so simple, not much excuse not to do your own maintainance
I can't give too much advice on CUTs, but for the tasks, you list; anything that feels comfortable to you and comes with a dealer you trust (even more important if you're not the wreching type), should treat you well. 4WD would be a bonus for tranfering a bit more power to the ground when conditions aren't optimal, but if the hills are your only challange, stability could [should?; I'm not always the best example of safty, so I try not to the police either /forums/images/graemlins/crazy.gif] be the limiting factor.
Now if nasty hills are the concern, check out the PowerTrac 1845; there are a few other brands out there with some nice specs as well, but PT's version is the only one I've seen in person, and I don't doubt their claims of stability. If "only" semi-nasty hills, how about a PT 14XX (25,30,45 HP). But, you have to be OK with a little wrenching of your own, as they sell direct. I'm still getting used to my 2445 (not the hill advange you'd get with the 14 or 18 series), but while nobody will try to tell you it's the best for every task; they're sure a neat compromise between a conventional tractor and a skid-steer (the latter of which I wouldn't put on hills).
Good Luck! /forums/images/graemlins/cool.gif