Windows XP logs in then immediately logs me back out again

[Marzo]

My computer has been infected with spyware and has come to the point where it won't let me log into Windows. When I click on any username it says it is logging in then logs me back out again. I have an Emachines computer with OEM pre-installed Windows XP Home edition therefore came with no XP CD, only a Restore CD which when used would result in my C drive being formatted.
I borrowed a Windows XP Pro CD(my edition is Home ~did'nt think there would be a difference.)from my friend and tried that yet when I accessed the Recovery Console it asks for an Administrator password to proceed. I have never added a admin password so is blank(it lets me click on administrator with no password request when entering safe mode).
However after leaving the password blank and pressing enter a message appears saying password invalid. Has anybody had a similar problem before? Is there anyway to bypass this or is there another way of recovering windows? Please help as I do not wish to resort to formatting the whole of C drive.

[degsy]

Welcome

Check the info at the bottom of this page
http://www.winxptutor.com/wsaremove.htm