Cannot install xp in Dell inspiron 1545 lapto

Hello,i was tryong to install xp in to my NEW dell indpiron 1545 laptop \. it was not redy to install it was showing some virus report . itried with diferent CDs .then also it was not installed .Then i tried for liscence version of Xp , it dint installed . now i hv installed Windows 7 , but still i want to install Xp. can i get any solution?
if im having 4 rives in my computer & i have installed w7 in 1st drive & XP in 2n drive. & after starting laptop in xp if im deleting setup of w7 from 1st drive will the laptop start in xp after restarting????