It all depends on what you want. If you want to live out someones either uneventful or alien fill life, pick Sims 2.
If you want to deal it parasite infected zombies with those really scary crazy axemen than pick Resident Evil 4.
Those who want to wander through the house waiting on someone to get out of the only bathroom you've got without wetting yourself get Sims 2.
Those who wish to wander through a house and run the risk of being mutilated by parasitic zombies get yourself Resident Evil 4.
Those who want the greatest risk to be a fire or starvation should enjoy Sims 2.
Those who want the greatest risk to be this almost unbeatable boss at the very end of the game should enjoy Resident Evil 4.
There is really no point comparing these two games in my personal opinion because they are vastly different. Sure, you have some choices in Resident Evil 4, but you cannot to my knowledge seriously change the course of events in this game. (Then again, I haven't played it so I wouldn't know.) Has my point come across? I hope so, otherwise I would have wasted all this time typing when I could be looking up stuff in walkthroughs.