Don't know if this will help, but here goes.

Assuming you have a Windows OS, the reason all your .zip's are Stuff-it, is 'cuz when you installed the program, it co-opted all the file associations it deals with (includes *.zip). To undo this, go into Options, find where it sets file associations, then re-set them for your preferences. You'll probably have to re-associate them thru your original compression program (Winzip, etc.) the same way.

As to not expanding them, there's a good chance that it is doing the job, just leaving the results where you don't want them. Probably in a folder within Stuff-it's main program group. Try right click>expand to, them browse to where you want the file un-zipped to. There is an option setting for this, also, but it's been awhile since I bothered with stuff it, so I don't remember the details (WinRar Rules). Sorry I can't be more specific.

As for Netscape, no clue. Don't like it, Don't want it. Opera's ok. IE6 is already part of the system.

Hope this helps.