WinRAR is crap. WinZip is crap.
Avoid these programs at all costs and go and download 7-Zip for FREE @ Download.com. 7-Zip opens everything. Even .ISO files. And it's SMALL.
Once you download and install, you can access 7-Zip by right clicking archived files. Right click your RAR/ZIP/COMPRESSED file, go down to 7-Zip, and select an option. You can Extract Files which will bring up a dialog specifying WHERE to extract, or you can Extract Here, which will automatically extract data in the compressed file where it currently is.
I haven't used WinRAR or WinZIP in like 10 years. Most people use 7-Zip.
Later.