Ok :-) Backup Exec needs an SQL server of some sort to work properly either MSDE or SQL. If SQL server was installed on the machine before Backup Exec was installed then it will have detected it and used that for its databases. However if nothing was there it should have installed MSDE. Either way it needs one :-)
I just checked on one of my Win2K servers running Backup Exec 9.1 hovered over the SQL icon and it shows it as SQLServer - so this is correct. I know however that its MSDE.
Check in Add/Remove programs to see if you see Microsoft SQL Server if its not listed then its definately MSDE.
I wouldn't uninstall or attempt to uninstall this component as its needed as I said above. So this should be ok now :-)
As for your multiple servers, each with a tape device and Backup Exec installed. The ideal way is to have a single media server with enough tape (and perhaps disk backup) capacity for all the servers. To accomplish this either install a single drive with enough capacity for all machines if they were full plus a little extra for expansion, next (and a better option) is to use an auto loader again with a high capcity device (this way if the tape becomes full during backup it will use the next available tape automatically - needed on over night backups), last and best option (most expensive) is to install a library with multiple drives (this would have the best expansion and flexibility).
As per the other post you would though need to install the Remote Agent on each server, plus ensure that any databases are covered by the relevent agent (SQL, Exchange etc).
I would guess in your case that each tape drive is big enough for each server only (i.e. a DLT 35/70 and hard disks of this capacity or bigger or somewhere similar). The cost of the options above could probably be covered by the licence costs of Backup Exec on each machine, or at least a proportion of it, and there would be only one backup server to manage which is much better and simpler.
Rob