Hmm, they help some, but it's purely damage resistance, not complete spell resistance. Ie, a ring of Frost +10% resistance means you get 90% damage from a frost spell rather than 100%. So whether or not that's noticeable...
I remember from Morrowind that any GOOD items you have to make yourself anyways. And to do that you have to get Enchanting 100% (which in MW involved going through this god awful dungeon to find the one guy who taught it, but he was always hostile against you, so you FIRST had to charm him, then talk to him, then buy training, then charm him again, then buy training again, then find Azura's star, then summon those Gold Giants, then kill them, just to make a dagger +5 Str.
Ofcourse, once I'd finally spent a day just creating items, my character was monstrously godlike.
One thing I really miss right now is a fucking NORMAL PC Interface. In Morrowind I had murdered this nobleman so I could nab his house, and he had like 12 tables in this one room, which I had set up as my trophy room. I had about 2 sets of Daedra armor, 5 sets of Glass armor, 1 set of every other armor, and like 30-40 combined Daedra and Glass weapons, all beautifully laid out over the tables. Just doing that was a lot of fun.
In Oblivion you can't do that because you can't manipulate items, because we had to create an interface designed for the fucking console