I have (seldom used) winzip too. I lost my Sims game a couple years ago and just got the mega deluxe. Now I'm downloading ALOT of zip files. I came across the coolest thing....The Sim File Maid. When I go 'Sim shopping' I save around 100 zips to my desktop. Once you install the Maid, all you have to do is open the program, click and drag the zip and drop it at her feet. She does the rest. Skins, objects, etc. Not houses though. If a file is missing something or corrupted she won't install it into the game. If it will overwrite another file, she asks you if that's ok with you. She keeps a log of everything she does. How cool is that? She installed 84 files for me in less than a minute!
You can find her here. Have fun.