Hi,
I'm a new owner of a Kubota B2910, but I would also recommend you look at all the offerings by NH, Deere and Kubota. I chose Kubota because I felt comfortable with my local dealer, my own research and recommendations of this group. "Tractorbynet" is a phenomenal resource and I suggest you do a lot of surfing over it's posts. You won't be disappointed.
My biggest comment regarding you post has to deal with your two boys wanting tractor rides. Of course they will. You, as a responsible owner, must tell them NO!!! These are not toys, can be very prone to tipping, are very heavy and in some cases can kill in moments. The standard ROPS and seatbelt will protect the driver only. In the event of a rollover and without a seatbelt, any passengers very likely would be crushed by the ROPS or the weight of the tractor. The closest I would come to giving tractor rides is to pull a wagon with the tractor and let the kids ride in that.
If you had a small lawn tractor, which has a much lower center of gravity (and they only weigh about 600 lbs. or so) you might give a ride on that. However, tractors in the class you most likely will be buying are very power tools, and NOT for play.
There are go-carts and things available with roll-bar protection, 2-seats, seat belts, etc. that would be a much better choice for a couple of growing boys. (In a couple of years, of course.)
I don't mean to "dampen" your enthusiasm about a new tractor and I hope I don't, but I do feel very strongly about safety, and these tractors are not toys. (Really, they're not, although we do have a lot of fun with them.)
Good Luck in your search, and please feel free to post any questions you might have on this group.
~Rick