Well it sounds like you have a couple of years of busy work ahead of you to prepare and plant lawns, landscape etc. After that it will mostly be maintenance, mowing, tree and shrub maintenance, fences and possibly drive way maintenance are the norm. And 5 acres is sizable peice of property to afford you plenty of tractor time.
Your already off to a good start by locating the dealers in your immediate area. As you stated your mechanical ability is minimal so dealing with a local dealer may be a plus. And as many here will tell you, the dealers attitude and reputation can be as positive an experience in your purchase as the products he sells. Asks these dealers if can contact some of the dealers if they can put you in contact with some of there customers for their opinions of both the dealers and thier products.
For the size of property you have and the projects you seem to be looking at, I for one would suggest a midsize compact utility 4x4 tractor in the @30 hp size. The main reasons to looking at this size would be. (1) This size of tractor usually has the weight (good for traction) versus a nice tight turning ratio for maneauverability. (2) This size of tractor has the ability to handle a fair sized loader. One that has a good max lifting capacities (min. 800lbs up to @1200lbs with a 60"/66" HD bucket and/or pallet forks), with a enough lifting height to be able to load a small dump truck or flatbed. (3) Enough 3pt hitch lifting capacity to handle decent sized implements, 7ft backblades or landscape rakes, 6ft box blades or finish mowers, and 5ft bush hogs and rototillers, (min. of 1500lbs lifting capacity). (4) And finally enough power take off (PTO) horsepower to be able to power the above mentioned PTO driven implements without bogging down. I would also like to add that this size of tractor is also quite often offered with a mid mounted finish mower (up to 72") as an option. By the way a front loader will probably be the best tool you will ever purchase, and your back will thank you for it many years from now. I mentioned the above implements and their sizes as these on avg. are the the most popular sizes for the most poular implements. That allow a tractor that size to accomplish the most work effeicently. Which is why most people buy a compact tractor in the first place.
One thing to think about is the type of transmission that you would like to have your new tractor equipped with. Hydrostatic transmissions have become a reliable standard among the industry leaders, and anyone can easily operate one. Kubota has a reputation for having one of the best. But Long/Land-Trac and Kioti are just now introducing their first ones based on tried and proven designs. And there are rumors that Mahindra will soon follow. ( those in the know correct me if I'm wrong here) As an alternative, if you can handle a manual tranny All of the manufacturers that you have mentioned offer good fully synchronised ones with shuttle shift and Live pto. Shuttle shift offers a seperate lever that just allows you to shift between forward and reverse, a very nice feature. While the Live pto allows you to shift gears without disengaging the pto, also very nice. Both features are great for beginners, as well as desired by those with experience.
As I am sure you have heard Kubota has a good reputation as a leader in the industry. However the other brands you mentioned, all have models that are built in South Korea, that are rapidly building a good solid reputation as being dependable and built heavy duty. and the Korean built tractors seem to be priced more reasonable than than the big three. Although with the current economy financing on new tractors appears to be at all time lows. Scroll down lower in the forums and you will find seperate forums for Kubota and Kioti, as well as a forum for other brands that will cover both Long/Land-Trac and Mahindra.
Remember that New Holland and John Deere are also leaders in the industry, and make great midsized compacts, and would bear looking into.
Well thats my point of veiw, hope it helps. And good luck tractor shopping.