The best backup to do would be using an ftp client on your local PC and then downloading all the files and burning to a CD-R. If you only have a few files you could use multi-sessions on the CD-R to keep updating the backup.
There is also a DH backup kept in .snapshot. You need to log in with PuTTY via SSH and then cd to the snapshot folder using 'cd .snapshot'. You will have to do this blind since the folder .snapshot does not show up with a normal 'ls -als'. But after having blind trust and cd'ing into the .snapshot folder you will see your backup files, which you can list and copy as normal. Note the folder name is .snapshot with a dot, not as I keep typing .snapsnot for some reason . Sniff...
If you search back through the forum you will see methods for creating automatic backups using 'cron'.
You can search the DreamHost WiKi for details about backups.
Opinions are my own views, not DreamHosts'.
I am NOT a DreamHost employee OK!! :@
You act on my advice at your own risk!