Dells and many of the larger OEM's use a special MBR which allows for a complete system reinstall from the hidden partitions so if you want to keep this feature, watch what you're doing with partitioning software! You've discovered Hiren's so this may not be a problem.

Likewise, you'll need to image the drive rather than any partition. I believe Hiren's contains imaging software such as older versions of Ghost. You can retrieve the executable and create your own bootable imaging media to suit your needs.
Whilst imaging to optical media is possible (Remember the original restore disks?), it's not really advisable. I use a spare SATA 2.5" drive in a cheap USB enclosure but you can also image over a network. If a dual layer DVD is fitted, you may be able to copy the resulting image to a 9Gig DVD later and retrieve from that.
Some time ago, Acronis DI was available as a free and fully functional download from somewhere like GiveAwayOfTheDay. It may still be kicking around somewhere. Ghost was included on the boot floppy that accompanied early OEM recovery sets.
You can use your Hiren's CD to recover the serials for XP, Office and perhaps other installed software and as long as you have like for like media (Office 2K3, XP Home/Pro OEM etc), you can reinstall using those serials. If you still want the Welsh language pack for Office, download the relevant file
here and run it after Office is installed.
Regarding drivers, these will be available from the Dell site but another recommendation here for an easy life is
Driver Pack Solution. This will install all necessary drivers in the correct order automatically and they'll be up to date.