Wobzip is a free online tool that can uncompress files on the fly. Wobzip can uncompress most compressed file formats like ZIP, 7z, GZIP, BZIP2, TAR, RAR, CAB, ISO, ARJ, LZHCHM, Z, CPIO, RPM, DEB and NSIS.
Wobzip lets you uncompress files residing on your computer as well as directly from a url. Once the files are uncompressed, you can download the contents of the compressed file as individual files or collectively as a .zip. Windows XP natively supports zip files and so you can easily extract the files without any use of third party softwares.
Wobzip can uncompress even compressed files which are password protected. Of course, you would need to know the password.