VERITAS Backup Exec for Windows Servers 9.1 build 4691.1 - excellent software but very pricey, as it's really aimed at the server market. Despite that, it will run on Windows XP Professional so long as you disable Simple File Sharing. I think they've finally made it able to back up remote Windows XP Home machines, but it won't run on XP Home. You don't have to be in a Domain environment; a workgroup is fine.
Unless I'm very mistaken, you can't use a Small Business Server version on Windows XP Professional - which is frustrating, because it's cheaper than the Server version and includes Intelligent Disaster Recovery (which means no need to reinstall your OS to disaster recover).
With the Server version, you can install agents on other machines on your LAN and back them up through that - including system state (the registry and so on). You can have unlimited agents on workstation OSes, but each server OS requires a separately purchased serial number.
Big Backup Exec installations need numerous serial numbers - over the versions, they've gradually required users to buy more and more option serial numbers. These days, you need a library expansion option serial number for each autochanger tape drive apart from the first tape drive with a changer. You need an agent serial number for each remote server OS (there used to be a multi-server option that worked with unlimited remote servers). The Intelligent Disaster Recovery option needs a IDR client access licence for each remote machine with IDR protection. Every machine that you want to use the Advanced Open File Option on also needs its own AOFO serial number. All this is without mentioning the multitude of agents for things like Exchange Server and SQL Server!
Backup Exec is supposedly pretty good at identifying reuse of serial numbers on the same network and objecting to it!
I'd like IDR on my machine, but really can't justify the additional expense. I've done a disaster recovery (somehow the C: NTFS partition was corrupted) using Backup Exec 8.5 on Windows 2000 Professional without IDR and it wasn't too bad once I worked out that you had to install the same OS Service Pack as you were trying to recover. That wasn't in the instructions anywhere!
Backup Exec won't drive CD and DVD writers directly unless you're using DVD-RAM - you have to use packet writing software such as InCD. It was historically a tape drive only package (I've got a DDS-4 drive in my machine) with support for a handful of magneto-optical drives, but version 8.6 introduced support for fixed backup to disk folders, and version 9.0 introduced support for removeable backup to disk folders.
My backups these days go first to a large IDE disk, and are automatically duplicated from the IDE disk to DDS-4 tape. Doing things this way means backups complete a lot faster, restores from disk are incredibly fast and don't put any wear on the tapes, and I have an added layer of redundancy.