Going to get Sims 3 Saturday! Eek! Could someone answer a few questions I have about it?

its a good game. but its a lot different than the sims 2, so some things i like better in this game and some things i like better in the other game... the only thing i wld think that wld make it lag is if your computer didnt have a lot of room on it or was older but other than that it should be fine... idk i think its a really good game and its deffinatly worth the buy