System backup

My Hummy's hard disk seems to be on the way out. I'm about to go away for Christmas so there's nothing I can do with it until I get back. Is there any way to create a backup of the current installation including all my packages and settings before I go away so that I don't have to install everything from scratch when I get a new hard disk after christmas? I'd really like to do the backup today in case there's a catastrophic failure while I'm away and I miss my chance, so swift answers really appreciated. Many thanks.