I have a Mac Mini that I would like to login remotely from a Windows XP laptop. Is this possible? What types of things do I need to do to allow remote connections from the Mac, and what type of interface will I be able to have? (Command-line interface? Or full GUI interface?)
You can enable the ssh daemon on your mac by going to
System Preferences.app -> Sharing -> (enable) Remote Login
You can enable screen sharing similarly with
System Preferences.app -> Shareing -> (enable) Screen Sharing.
If you are not using the Apple Remote Desktop software, you'll need to do the extra step of clicking on the Computer Settings button, and supplying a VNC password
This isn't the free option, but if you have two macs running Leopard and a MobileMe account you can use Back To My Mac to connect to the other mac's desktop. Here is a quick screencast of this feature.
I use these this web site. You need to sign up but you can access you choosen computer. I use to to fix my dad's computer. I use the basic free versio. Works fine with both Mac and PC https://secure.logmein.com/