If you can walk you can snowshoe! You can look up a lot on the web. Many set a criteria on weight. Get this size for this much weight. Don't forget to include your weight and all the weight of boots, cloths, packs, you might have on too. Very Important is that different snowshoes go better in different kinds of snow and terrain. Also Traditional shoes (wood) or moderen (metal). I have three pair of snowshoes, green mountain bearpaw, 5.5ft ojibway, and 8X25 moderen. I perfer wood snowshoes but metal has its place. Based on what you said you would use them for I would choose the moderen metal snowshoes. For walking the dog and snowmobil backup its a toss up. 8X25 would be nice and light, good on packed trail, not as much floatation as a bigger shoe. 9X3? shoes would give you more flotation and versitlity, better for off trail or new snow. If your machine gets stuck and your going off the trail your going to want more floatation. Bindings are another area. If you buy metal they usually come with some kinda of buckelt and pull strap type binding. They should be adequate. Brands. Look on line, lots out there, all spending prices. Poles are nice at times.
Snowshoeing is a blast once you get started you may want more adventures in the woods in winter!