I actually have more memories with The Sims 3. (Even though it was so buggy, crashed millions of times, lost saves over it and everything)
I simply bought a lot more expansion packs then I did with the Sims 2, and I really enjoyed them. I liked Nightlife, living in apartments, and entire city, although it was laggy as hell.

I love being a superstar performer, designing your stage, although I wish it was explored deeper, and I actually liked exploring China, and Egypt.
Although Sims 2 is arguably the better game, I played The Sims 3 a lot more. So my votes goes to the Sims 3. The Sims 1 is a fond childhood memory, bringing my own house to life, and lighting firecrackers off in the house to burn my house down. And The Sims 4, I enjoy it, but can't help but feel the lack of gameplay, and nothing that blew me away, or excited me to a point of it overpowering the previous installments of the game. That could change with the release of new and exciting expansion packs (if that happens, and we don't just get "gamepacks")