[banjoeball]

That depends on what you're backing up. If it's just your emails and contacts, even your 'my documents' give it a try, it probably won't mess anything up.
But don't back up/restore the system settings unless it is the same model of phone, running the same rom. Unless you want some problems.

But the general idea with SPB Backup is that you back up your files into a self-extracting .exe that you just press-and-restore.