Uninstalling Sims 3

@lil_candie91  All of the packs in your Origin library will continue to be available—your account owns the content regardless of whether it's on your computer.  If you ever registered Generations, which you likely had to do if Origin lets you play with it, that EP should show in your library as well.  If it doesn't, you can still add its code to your account now.  The code is the same one (on the back of the insert in your CD case) you would have originally used to install.  If you don't still have that, you can find it in your computer's registry:

https://help.ea.com/en-us/help/the-sims/the-sims-3/manually-uninstalling-the-sims-3/

When uninstalling TS3, it's a good idea to clean the registry (as described in the link above), either manually or with a tool like Piriform's CCleaner (free).  Otherwise, if you ever reinstall, those registry entries can get in the way of your ability to launch the game.  But of course, be careful not to delete anything else in the registry, which has other files that are necessary to make your computer function.