We need to install Backup Exec software to our SQL server which is already running our live SQL database etc.
Why? grab a spare desktop, stick in a SCSI card, connect your drive/library. With today's processors, you will be much more likely to face network bottlenecks than processor bottlenecks The SQL serial includes one RAWS, so you'll be able to backup the SQL server .
I'd prefer an MSDE database My thinking is that if you put the database in an existing instance, you have to have SQL back before you can restore, but you have to have BackupExec before you can do a SQL restore , but ..