Sims for PC are the main games. The first Sims ever to be released was in 2000, The Sims 1.
From what I've been reading, Sims Freeplay seems to be goal-oriented and not really about the Sims themselves, although babies and toddlers in Sims Freeplay have tons of adorable things to do. Toddlers in Sims 3 can’t do half the things that they can in Freeplay, but other than that, Sims games for PC are far superior.