Backup or copy

I currently use Arcserve 11.1 to backup up my NW6.5 sp5 server. I backup to
an external harddrive ( my solution to a failed tapedrive and not having a
couple of grand for a new one)
It takes 22 hours (about 90 gig) to backup and the resulting file doesn't
appear to be any smaller than the source.
Is there a way to just copy the server to the external drive that maybe
faster and and easier to restore?

Thanks