i am super new to shooting and i have a few questions about my new 12gauge. i know these are stupid questions but i'll ask em anyway.
I'm not terribly knowledgable about shotguns, but I'll try to help. Someone else can correct me if I goof.
what are the lightest recoil shells you can get,
Assuming you're only using 2.75 inch shells, I'd guess the larger the shot, the heavier the recoil. Slugs have the most recoil. For self-defense loads (which are often 00 Buck), there are "reduced recoil" loads available.
can you hunt squirl or rabit with a 12 gauge
Definitely. A load with #8 shot should be appropriate.
is it really a bad thing like i was told to dry fire a shot gun
It's better to avoid dry firing any firearm a lot, since that can do some damage to the firing pin. (Glock handguns are an exception.) If you want to dry fire the gun, it's best to buy a 12 gauge snap cap and put it in the chamber.
what happens when you fire a blank basiclly a shell that the beebees have been removed.
If there's still a primer and powder in the shell, then a huge amount of gas will shoot out of the bore. If the shotgun is a semi-auto, then it might not cycle properly. Be careful not to point the shotgun at anyone even if it only contains a blank round (or even no round -- just to be safe).
are heavy dove 1255 velocity shots heavy kicking?
It depends on how big you are and how heavy the gun is, but that sounds like a relatively tame load.
Recoil really isn't anything to be afraid of -- just hold the gun firmly to your shoulder. Shooting a lot of high-recoil rounds from any gun can be tiring and could bruise your shoulder, but it shouldn't damage you. Just rest if your shoulder starts to ache. You can also buy a recoil pad for the stock if you really dislike the recoil.
is the kick really serious from a 12 gauge or something you quickly get used to?
It's pretty stout, but again, it depends on the load, the gun's weight, and your size. It can be unpleasant if you're not a big person, but you can certainly get used to it. Many smallish females have no trouble shooting a 12 gauge and compete regularly in skeet shooting, etc.
By the way, there's more information here:
http://www.alpharubicon.com/leo/shotgunpace.htm