dont use Win XP remote assistance unless your a wiz with firewalls.
It uses the same port as the MSBlaster 32 worm.
Also to use remote assistace with XP the host has to be an XP pro
So an XP pro cannt dial in to an XP home / win 98 95 etc, but you can do it the other way round
using dail up will be slow as feck but its possible
Get WinVNC and its free and prettys secure provided you use a password
lol
This is what I use
http://www.realvnc.com/download.html
BTW you need it installed on both machines