Not sure about the 'help progs' part but it could be that you just need to install the correct Vista driver for the printer. This may be on the printer installation disk supplied with the printer. If it isn't, go to Dell's site and look for the 'Support' or 'Driver downloads' section and find the driver. If you have difficulty with this, post the model number of the printer here.
If you really want to go back to XP and have a full installation disk, it would be a case of putting the XP installation CD into the CD drive and then starting the computer. This will start the installation process. It could be that you'd first need to go into the computer's BIOS settings and change the boot sequence for this to happen.
The installation process will format the hard drive (wiping out Vista) and then start installing the XP operating system. However, when XP is up and running, it would still be necessary to install the printer on the system using the appropriate driver. This usually needs doing whatever the printer or operating system. Windows 7 may be better at running printers without the need to install an additional driver but I think Vista and XP will always need it doing as an extra.
My own inclination would be to persist in getting Vista working properly, rather than go back to XP. If the above seems a more involved than you are prepared to go, perhaps consider seeking local help, or take the computer and printer to the shop where the computer was bought and ask for their help.
Edit: Typo
Edited by tellywellies (Thu Oct 01 2009 10:29 PM)
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