1) Bedding is the contact between action/barrel and stock. Some common types of bedding are: inlet - where they grind down the stock till you get a perfect fit, glass - where they put epoxy with fiberglass bits to get a uniform fit, and pillar - where they have pillars that stick out from the stock and attach to the action/barrel.
2) I believe most rifle manufacturers use two lugs. Browning has three and Wetherby has nine. With two lugs the bolt has to move up 90 degrees before you can pull it back. With Browning's two lug, you only have to move it up 60 degrees. With Wetherby its like 56(?) degrees.
3) AccuTrigger is Savage Arms proprietary trigger system that makes easy from the user to adjust trigger pull themselves instead of having to pay a gunsmith to do it for you.
4) There are short, long, and magnum actions IIRC. This refers to the lengths of the cartridges. The longer the action, the more you have to pull back and push forward to put the new cartridge into the chamber.
5) The rifle twist rate is the length of the barrel that the rifling makes one 360 degree loop. The shorter the length to make 1 turn, the faster the bullet should spin coming out of the barrel.
6) Your choice, I am in the market for my first rifle also, and I heard good things about those three companies as well as Browning, Ruger, Sako, and Wetherby. I decided to stay away from Magnums for my first rifle because its a bit of overkill for deer and those fat short mags usually means less cartridges in the magazine
