I know computer is infected pls help

I know my other computer is infected with spyware specifically the winlogon.exe (sighhh) my son was playing a game on my computer and somehow the NAV auto protect became disabled. Now my computer wants to keep sending mass emails to peeps but it times out and also eventually kicks off the internet connection.

I know I am to do Read Me First and that is what I was doing was in Safe Mode and up to Counter Spy (Spy bot found smitfraud and something else I can't remember the 2nd one) and I fixed those and went to run counter spy and it said I had no Internet connection as it needed to run an update so I went to restart my computer so I could connect back to the internet let it run updates and then go back into safe mode. It was sitting there logging off for 5 minutes so I pressed in the power button on the tower and now my computer keeps rebooting to a black screen where I can choose Safe Mode, Safe mode with networking, Safe mode with command prompt, last known good configuration, and boot normally. I have tried all those and it still brings me back to this screen it just keeps cycling there. If I choose Safe Mode I have to press F8 to get into Safe Mode and regardless if I select safe mode, or the other 2 safe mode options it will scroll thru things and then reboot back to that other black screen.

Right now I am on computer #2 ...
What do I need to do to get computer #1 back to where I can boot normally???
Thanks,
Darla

 

Never mind I contacted the computer manufacturer and they told me that unfortunately there was nothing I could do except do a complete restore to my computer and restore it to factory state.

Now I do have a question regarding backing up my computer.... how do I do a complete back up to a CD on a nightly basis so that if this should ever happen again I have that backup because I downloaded pics from my camera last night and was going to put them to a CD today and I lost those pics and they were important pics.

XP home is my computer OS

Thanks.
Darla