Maybe this helps :

Open Notepad and copy paste the following into a blank notepad file:

ren *.zip *.

Save it as [something].bat where [something] can be anything. Run the file in the folder with the zip files and it will remove all .zips from all files in the folder.

Be careful that there are no real zip files in the folder though. This file will remove every zip extension from every file in the folder.
Didn't test it myself, so be careful the first time. There are tools for renaming too see http://www.facialforum.net/showthrea...nd-downloaders for an example.