Do you want to make sauce, stewing tomatoes, salsa? I have always used Roma-- I quite like them for canning. i also freeze these whole, with the peel on. After thawed--just squeeze the fruit out of the skin and you have perfect stewing tomatoes.
Yeah, what miss_thenorth said. Plum tomatoes of whatever sort (I don't honestly see much difference among varieties, except for yield and other 'growing' issues) if you want thicker type tomato sauce. (P.s. - if you want a smoothish sauce and dislike mashing or grinding, try seeding them, then just grating them off the skin using the medium-big holes on a metal grater, it does not work too badly and is MUCH faster since you do not need to dip-in-boiling-water-then-peel. Then cook down and can as usual).
Or if you like a 'wetter' canned product (either canned tomatoes or stewed tomatoes), you get about the same results IMO from either plum tomatoes or any good-flavored 'regular' tomato (if you have read my other posts you will not be surprised when I recommend Early Girl <g>), I don't honestly think variety makes a big difference although doubtless some will disagree.
Unless you want to freeze and *then* can, you want something that will produce a large yield relatively all at once (i.e. a determinate or earlier bearing variety). Preferably not at a time when you are going full-bore canning *other* garden produce, supposing that can be predicted
Thank you for the good advice. I'm mainly interested in stewed tomatoes, though I would like to can some home made sauce if I have enough to do so. I've never tried freezing, I have always been told that tomatoes don't freeze well. If I could have the same good results I would do that as well.