You don't want to decompress it, you want to compress it. As to whether or
not anything can compress it down to make it fit on a 700MB disk depends a
lot on whether or not the file is already compressed. What type of file is
it?
There are a number of free compression utilities available, including one
included with Windows XP. In XP you can right click on the file and select
Send To->Compressed (zipped) folder. This will compress the file. If that
doesn't get the level of compression you need, you might try 7-Zip from http://www.7-zip.org/.
--
Tom Porterfield
MS-MVP Windows http://support.telop.org