It depends on what you want 'faster' (hopefully the game will be around long enough for everyone to catch up and collect everything).
All the mini-games in the Foster's House give out pics for the photo albums, furniture for your room, buddies, music and hats.
The mini-games at the Mall give out furniture for maybe 2 room themes (I can't remember exactly), buddies, tickets, movies at the Mall, pics with your Best Friend (enter someone's code first) and music. The tickets will give you "vehicles" and costumes that you wear. It's been debated if these vehicles make you move faster in the game or not.
All the toys/games in Mac's room are just for kicks. They give you nothing for winning/losing, there is no high score to beat, and no collectibles. Some people like them, others think they are lame and not worth bothering.
For me, personally, I finished all the games in the House, first. Then I did the arcade at the Mall. Now I'm working on the last few toys at Mac's house. My middle daughter is trying to catch up also. She's finishing up the Mall games, then will go to the House games. She only has a couple from early on to unlock, but didn't care about finishing the Imaginary Friends Album before getting the pogo stick and Loren costume.
~Vicks