On my pc with xp I use TightVNC and on the n800 I use VNC viewer.
It takes about four minutes to be up and running.
Go into your apps manager on n800 and install VNC viewer. Then go to this website below and download TightVNC. Follow instructions on app and your up in a few minutes controlling your PC with XP. The critical part is getting IP address of pc and IP address of n800(they might be different). Setup password and you are up and running.

https://garage.maemo.org/frs/downloa...N800_armel.deb