The Sims 2 can be quite overwhelming the first time you play it because it is quite a bit more challenging than TS3 or TS4. My suggestion is to start out slow. Start by creating/playing a single sim or a couple, and try out new features as you go along and get used to the flow of the game.
I remember the first day I played the game, I created a couple and had the wife get pregnant. Pregnant sims are HARD. You constantly have to watch their needs, and they can't do much more than eat, sleep, or pee. Then once the baby was born, I wasn't really used to juggling needs/gameplay yet, so my sims were constantly falling asleep in their food while the toddler screamed and threw tantrums in the background. I was so frustrated but I couldn't put it down, it was that much fun.
If you check out the thread New to Sims 2, which is similar to yours, I posted a long list of things I have yet to accomplish in the game that you might have fun trying out.
Good luck and have fun!