About a year ago, I backed up all my win xp sp1 data. This was copied to a 650MB CD-RW disk. On my desktop I am shown a shortcut to this backup file which gives as total data 9GB. Isnt this wrong ? Also am I supposed to update this backup file or should I delete it and make another newer backup file? Is it necessary to have the backup file on the computer, if you have it on CD-RW disk?
If you did back up everything, it will be a damn sight larger than a 650mb CD-RW.
The whole point of a back up is to have something from which you can restore your data if your PC packs up. Therefore, any back up should be made to a media which is kept separate from the PC.
For what it's worth, I do a back up at least once a week. I use the XP back-up facility for a PC which has 4 users. I back up 'Everyone's Documents and Settings' to a removable ZIP disk and the size of that back up is around 210mb.