If you have LAN (or at least more than 1 computer in your home), you can experiment yourself. Try to use Windows-XP remote desktop or install third party program such as RemotelyAnywhere, PC Anywhere, etc. After you install the software in one PC, then use the client software which is usually comes within the installation software to remote the PC.
If you are using RemotelyAnywhere, you don't need to install client, because you can use any web-browser which support Java as the client.
If you are using Windows-XP remote desktop, the client already reside in your Start Menu. Access it from here:
Start -> All Programs -> Accessories -> Communications -> Remote Desktop Connections
PS: Make sure you already setting the other PC to allow this remote.
Use Windows HELP for detail at:
Start -> Help & Support
Use Keyword: Remote Desktop
Happy learning :)