Cindy, please let me add my take to the excellent advice you already have received from Jason and Bob. No matter which tractor you buy, there are several things you have to consider when handling 900 lb of cargo on the FEL. The three primary ones are:
(1) How far out on a truck/trailer will you be reaching?
(2) Will you use pallet forks to keep the load close to the loader's pivot points?
(3) What kind of surface are you going to be moving the load on?
The NH 16LA loader that fits on the TC35/40 tractors will give you quite a reach advantage over the 14LA loader that would be on a TC33. The tractor is taller and the physical dimensions of the loader make it able to reach a load without running the nose of the tractor into the side of the truck or trailer. If you undload pallets from the back of a flat-bed, you'll appreciate this advantage.
If you get a quick attach loader with pallet forks, your loader's ability to lift heavy loads is substantially increased over the kind of pallet forks that clamp onto the bucket. Those clamp-on forks are great, but if you are lifting 900 lb generators and the weight is centered out 3 feet from your loader's pivot points, you may struggle to lift the generator even with the 16LA loader. I'm sure it would likely be impossible with the 14LA. Make sure whatever tractor you buy, you get the loader configured for lifting as close to its maximum weight as possible.
Finally, once you get the generator off the truck/trailer, what are you going to do with it? If you are unloading in a paved parking lot, that's one thing, but if you are unloading and then hauling over rough ground to a jobsite you better have a tractor with enough counterweight to keep from tipping over on it's nose. Essentially, you have to be safe for both the operator and the load you'll carry. The extra size and ability of the TC35/40 will be another big advantage in this situation. I think you should also seriously consider a hydrostatic transmission too. The ability to constantly vary your speed and change directions without removing your hand from the steering wheel and loader joystick is a tremendous advantage when handling cargo. You can concentrate your attention on the load rather than operating the tractor.
So, for the job you describe, I'd certainly recommend the TC35DA or TC40DA as the tractor of choice. If the weight was only 500 - 600 lb, I'd say the TC33, but I believe you will never regret the larger tractor for handling 900 lb generators. /forums/images/graemlins/cool.gif