Right click your computer, Properties, Advanced,In Startup And Recovery click Settings, Unclick Time to display list of operating system.
(If it still starts up with the old boot screen go though all that again and this time pick Edit the startup options manually , and delete the standerd one I think its this one
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Home Edition" /fastdetect /NoExecute=OptIn
It should be obvious which one,