I feed Most of my snakes rats some of the smaller ones get mice.
80% of my snakes get Frozen thawed rats. These rats have been pr-killed humanly. I get them packed frozen then I let them sit thaw and the dance them in front of the snake untill they bite. I do this for my big boids. For my 10ft boa I have too feed her BIG Rats or small rabbits. Well a live Jumbo rat fighting for its life can do a lot of damage with those teeth. Its easier on everyone to feed large prey pre-killed.
As for the best started snake it depends on what size your looking for.
If you looking for a really small snake mainly in the colubrid family try
-Corn snakes
-rats snakes
-King snakes
These snakes stay around 4-5ft some, like the rat snakes, can get 7-8ft. These are slender bodied snakes. I dont like the small snakes from my experience they tend to be more nervous and nippy.
If your looking for something a bit bigger but not too big try Ball Pythons. I think everyone should have a ball python, I have 5. They get about 4-5ft they are a heavier bodied snake can get about as thick around as a can of cola. I have never met a ball python I didnt like
If you want to dive into some bigger. Try the snake pictured. He is a Red tail boa sub species know as columbian boa. They are two different but closely related snakes. There is no way to tell really in pet stores which on you get. They average out about 10ft. Internet will tell you 13-14ft. But this is extremly rare I have never met a red tail over 10ft. These are great boas and if you can get them small and work with them you'll have a nice, long relationship with a kick ass snake. They are gorgeous.
I wouldnt recomend much larger for a begginer. Burms get around 16-17ft and retics close to 20-25ft. They are not good starter snakes. But i suppose if you get them as babies and work with them you learn to trust them, but to me, and im a big girl, 6ft 190lbs a 10ft boa is enough for me to handle alone.
some of my snakes
columbian boas
10ft
5ft
Ball python