1. The Sims 3 (for the computer, not the video game) - I know I just put a big "nerd" target on my back, but I don't care! This game is so much fun! I haven't played in a while, because I just don't have the time anymore but when I do play I play for hours! If you haven't played it before I beg you to give it a shot. I know it looks dorky, but aren't dorky things usually a lot of fun? :)
2. Pay Day - I have not played this game in years and years but I still remember how much I loved it! I liked to see how much money I could get (duh, wasn't that the point?!). I played this a lot while babysitting. Those were the days!
And close runner-ups are Life & Monopoly! I love the classics!