How Do I Connect My Windows Xp Computer To My Friend's Vista Computer?

You could attempt to fix it remotely. By this you would have to enable (on her end) The remote access.  Unless you are a certified service tech, or a tech specialist going to school I would not attempt this.  Vista is a pain in the hind quarters and most likely will not let you do anything anyway. I would try to walk it through with your friend over the phone.  And if that doesn't work, then your friend really needs to call tech support. Don't settle for anything less than a tier 2 tech. Tier 1's are just following a script, tier 2's know pretty much what they are doing, and tier 3 are God's. I wish you luck

I think you would like to connect your computer with your friend's computer over the internet. For this purpose you need IP address of your friend's computer. Go to start>programs>accessories>communication>remote desktop connection. It will ask you the IP address and would connect you with your friends computer. Be sure that the remote desktop connection is allowed on both computers. You can activate it by right clicking on 'my computer', go to properties>remote and select the appropriate check box. Also you have to turn off the firewall.

I asked a friend of mine with a microsoft certification and he recommends having someone with a background in IT doing it for you.