The sims 2: Free time show a really good potential, that, in my opinion, Ea games don't used it very well
The leisure activities is a great add-on on the game, most of them are too simple and don't have many benefits. I'm not going to tell spoilers, I think it isn't right. On the other hand, it brings a good quantity of spare time activities, as well, you can enjoy a day in the park or stay all day in front of the television. You can unlock news things to do about the activity with enthusiasm, no problem already, some zodiac signs (is it right?) have like a pre-dated enthusiasm, so the sim will learn faster that leisure time activity. Well the problems begin when you realize that you lose enthusiasm too fast (about a point a day) and it's almost impossible to have 3 our 4 "enthusiasm" you can control.
If you have a combo (When you have all Sims 2 expansions) the free time expansion pack can be a good choice, as you have too many things to do, you won't remember to focus on your free time.
Overall you should buy The Sims 2: Free time when you have more expansion, because itself, don't worth