Backup media W/Nero

Its been a long time since Ive posted, and this is a rather simple question I've been unable to figure out, quite embarrassingly, I might add:-o

Anyway, my situation is I have a 4 drive external backup (each drive has an identical drive in my computer, if your curious, its 2 1.5TB drives, 1 2TB drive, 1 3TB drive, 8TB in total. I like pron (j/k)), which I all my media to occasionally. I leave it unplugged, in case of power surges, I want my data to survive, even if my computer and everything else plugged in is fried (A lightning strike nearby will overload any circuit breaker and fry everything in a split second).
So, I want a simple way to plug it in every now and then, and have the drives sync with the ones in the comp. I've been trying to use Nero back it up 5.4.19.100 (nero start smart 10) in windows 7 ultimate 64 bit. However, I cant seem to find a way to make it copy over the files (updating changed ones and adding new ones) *and* delete the files on the backup that I have deleted from the computer. It either restores the deleted files back onto the computer from the backup, or doesn't delete the files on the backup.
As I often shuffle things around, this could result in huge headaches. my backup will become 'overfull', or my computer.
I would like a way to do a smart update sync backup thingy, so it doesnt have to copy over data that is already there (so i dont want to do a whole drive image each time). A full backup takes a day or so, so I dont want to do that every time. If I only add a hundred gigs, it should only write a hundred gigs, not the full 8TB, lol! And it should delete files from the backup Ive deleted from my comp.

Can anyone show me which settings in Nero I need to use, or recommend another program (doesn't need to be free, I'll pay for the peace of mind, I spend too much on the harddrives to really think about without crying, lol).

EDIT: I also want the files to be accessible from any other computer; that is, the file structure is intact, so it can be browsed normally

Thanks anyone for the help!

PS I am very thankful for the help; it seems like such a simple issue, I should be able to get it myself. And I haven't contributed in awhile, I shall have to rectify that as classes are out atm!

ChemC