Blue tooth will only transfer 1 file at a time and is therefore almost useless for real networking.
To net work two machines
if directly you need a crossover cable.
If via a router
two cat 5 patch cables, one cable from each machine to the router.
or a wireless card / dongle in each machine
Choose a name for your network. Most businesses use some form of their business name, while people setting up home networks often use family names. Write the name down exactly as you spell it.
Adjust the workgroup name on the XP computer. Use the "Start" button, and then right-click "My Computer." Select "Properties." Click on the "Computer Name" tab to reveal the workgroup name. You can change the name by clicking "Change" and typing the new name in the "Computer Name" field. Save changes by clicking "OK."
Change the network name on the Vista machine. Use the "Start" button, and then click "Control Panel," "System and Maintenance" and "System." Look for "Computer Names, Domain, and Workgroup Settings" and click the "Change Settings" option. Go to "System Properties" and click on the "Computer Name" tab. Select the "Change" option. Type the network name you created in the field next to "Workgroup" in "Computer Name/Domain Changes." Save your changes by clicking "OK" and allow your computer to restart.
Set the Vista computers to a private network location for your local network. Go back to the "Control Panel" from the "Start" menu. Select the "Network and Internet" icon, and then click "Network and Sharing Center." You should see your network name and a designation next to the name. If the designation is "Public" or "Domain," click "Customize." Change the network type to "Private" in the box next to "Location Type" in the "Set Network Location" field. Save your changes by clicking "Next" and "Close."
Test your network to see if your XP and Vista computers are working together.