The Sims: Deluxe Edition combines the original game with the first expansion pack, Livin' Large, on to two CD's.
Included in this new expansion are all the items from the original game and the first expansion, 25 new items exclusive to Deluxe, 50 new costumes/skins, and a new program, The Sims Creator.
The Sims Creator allows you to customize every aspect of your sims. Shirts, shoes, ties, accessories, logos, tattoos. Build whatever kind of Sim you want, then import them into the game.
This newest expansion is good by itself, but it's recommended that you have all the other expansions to have full playability.