Upon reading this Help and Support article by Microsoft, someone posted in a forum how you can play games etc while your XP intall is running.
Ok so i looked into the matter: Once XP has placed the needed files we can do just about anything through a CMD window by pressing Shift+F10 during the GUI section of the install.
How? you may ask-Lets say that we are in an XP install and we are bored and feel like a nice game of pinball.
We wait untill the nessasary pinball files are installed
Press Shift+F10-And type the following…
“Bingo” we are up for a nice game while we wait-and you can do just about anything.
-Patrick S (Help sourced from HERE )