Ubuntu is a great solution for a desktop OS. But it still lacks in some key areas.
For example, it doesn't ship with a nice GUI backup util.
While Windows honks will point out that Apple's time machine simply puts a pretty face on the shadow copy tools that had been in place since Vista and Server 2003, Linux honks will remind you that rsync has been doing basically the same thing for like forever.
The problem is that rsync is not a nice GUI app.
But Back In Time is. And I think it is a great solution for backups on Ubuntu. While not in the default repos, it can be installed with a .deb from their site.
Check it out.