As of July 2014, every owner of The Sims 2 and all the Stuff and Expansion packs can download from Origin The Sims 2™ Ultimate Collection for PC. That’s a >10GB collection of all the Sims 2 you can have in one single download, one single installation.
Download, install and you are ready to play. No more endless one after the other installations, no more patches. Click on the Desktop icon and enter the Sims world. That's it!
Once you choose the neighborhood of your preference you will have to start adding things, like a vacation destination, university, down town, weather control, etc.