I can only speak for the first. There are two reasons for oil loss--1 is faulty seals and or piston rings. This will lead to the oil making its way down to the combustion chamber and getting burned along with the fuel. --2 is loss from gaskets like the valve cover, oil pan,. etc.. If you see oil dripping down the side of the engine, its the latter, If you find oil drops under the tractor after sitting some time, its the latter. If you lose oil and you don't see signs of oil out side of your engine, its the former. If you have 2000+ hours on the motor and you are unsure of how it was maintained through the years, you are probably looking at an engine rebuild in the future. with regard to engine stalls, it can either be the engine needing tune up or your spindles are worn and cause excessive friction.
The more you tell us, the more we can tell you. Did the problem with the engine stalling happen when you started using gator blades? Or have you been using them for years and it just started? Also, oil loss is gradual. I cannot imagine you just started losing oil after the last use of your tractor. Has it been happening for some time now? Has it been getting worse and worse? Do you see blue smoke when you run the tractor? The problems you are having are easy to determine (may not be easy to fix!).