My best advice is to start over. Bookmark the sites you use regularly and then delete your DL folder. After you have deleted it start with bodyshop. Get clothes, hair, makeup, ect. Before you download any of it think though *Will I really be using this?* If the answer is no or maybe don't download it. Then do the same for Furniture and build mode.
*I know its really hard to pass up a good hair but hey sometimes you have to.
*Also when downloading from your Bookmarked sites don't spend too much time on one site. Go through and look. If site A has a good hair but its high poly then maybe Site B will have a better hair low poly
*If you have 2-5 living rooms sets don't download any new ones. Thats too many. Can we say sloooooooow.
*If you find yourself not using a hair you thought you would then delete it. THat gives you room for a new hair that you know you will use.
*Sometimes you forget all of this and start downloading all crazy. At the end of every week check your DL folder (Sims 2 CI is the best) and get rid of stuff you really don't need..
*Think about how your sims get around. If you don't mind using a taxi then don't bother downloading custom cars.
*(What I do) I have houses that have all maxis stuff and then I have houses that have custom stuff. So whenever I want to play maxis house I take all of my d/l out so that the game will run smoother and faster.
*****These are some of the things I do and my folder went from 3.78 GB to 269MBs its not as bad as you think. I have very good *Peggy* hairs in my game and I also have some very nice *Windkeeper window sets* I also have bunches of *Icedmango and heleane make up* When I put my furniture in my folder goes up to 400+ MBs. So watch out for furniture.****** If you have anyquestions don't hesitate to ask.
I'm very OCD-ish I can get you all organized and straightened out