The files you are looking for are in Program Files. There will be a copy of the EA folder in there with everything. For future use, you can also make copies of all of the fresh neighborhoods and put them in another file on your desktop or a flash drive. I do both. But my neighborhoods are clean neighborhoods I created.
If you aren't using clean or custom neighborhoods, you can just generate new ones simply by changing the game folder in documents to Sims 2 Legacy.bak. Then when you start the game, it will generate a fresh folder. Then you can go into the old folder and copy over your mods if you have them and replace the settings files to keep the settings you had. Once you've loaded up and confirmed that everything is good, you can delete the bak file.
