Start up disk full due to backups
My guess is you had .Mac and ran Apple's .Mac backup tool as described in this article.


http://macdevcenter.com/pub/a/mac/2005/09/23/backup3.html?page=1


If the files have orange or purple umbrellas as icons, that would be a good clue that they came from that Backup program. Looking at the dates of the files might also help you establish how old they are.

These are probably very old and you could delete them or move them to an external drive to free up space on the drive, but it would be prudent to be sure before deleting them.

Turning off Time Machine would delete any local backup file store, and you can force that by running sudo tmutil disablelocal but those backups get stored on a separate /Volumes/MobileBackups filesystem and are normally very well hidden and don't use any incremental file naming scheme like the older software did.