In what way? Fallout 1 and 2 share the setting, but play entirely differently.
I rented Oblivion: Elder Scrolls and it felt exactly like FO3 or NV. Just a different time. And i had a little bit more fun playing it.
Yes, there are. All 4 main Elder Scrolls games (not the spin-offs) use similar gameplay, as they are both created by Bethesda. Elder Scrolls Skyrim is being released on November 11, 2011(11/11/11) and it, too, will have similarities to the recent Fallout games.
in terms of shooting RPGs Borderlands is a great game, decent RPG game structer all based on stats but with fast passed 1st person shooting, decent legnth game and now its a GOTY so comes with all DLC (alos has a comprehensively extensive Wikia dubbed wiki borderlands.
Edit: Borderlands is NOT an RPG. The only reason people call it an RPG is because you have a skill tree and you talk to the same people to do the same collect/kill quests over and over again. Why, people like it, I'll never understand. And their choice of color is god awful. Greys and browns as far as the eye can see.
Mass effect 2 is also very good, huge game area, not as long as FO3/NV, but loads of missions to do, great charactors, good stories, and the way you play it will determine how the 3rd one (out later this year) will play.