windows xp problem

hi all!
i am facing a critical problem in windows xp included service pack2. fristly when i turned on my computer system logon with administrator user automaticaly,after this i am unable to click any icon on desktop or start button and taskbar unproper load. Now i press ctrl+ALt+del and log off from this user and again logon from this user then i am able to click desktop icon and other actions taskbar also properly load.
please solve this problem
thank you all