My /etc/fstab looks way different than yours - so I'm not sure how to edit it.

Do I just go ahead and add 'usrquota,grpquota' after the word 'defaults' on the line for mount point '/'? 

I also ran the command 'uname --all' to show you the system I'm using: it's Debian 4.0 on i686 using Xen virtualization at my VPS hosting provider. 

myserver:~# uname --all
Linux myserver 2.6.20-xen-r6 #2 SMP Wed Jan 16 19:43:41 CET 2008 i686 GNU/Linux

myserver:~# cat /etc/fstab
# Hard file systems.
/dev/hda2       /       auto    defaults        0 1
/dev/hda1       swap    swap    defaults        0 0

# Virtual file systems.
none            /proc   proc    defaults        0 0
none            /sys    sysfs   defaults        0 0

Thanks for any suggestions.