XP, no screen change Intermittent problem

Hi all,

My problem may not be new but I cannot find a reference to it anywhere!
OK I am running Windows XP Sp3 on a Dell 630m laptop. My problem is when I try to open my browser, Google Chrome nothing happens, that is to say the mouse arrow still works, but nothing else, oh I can open the start button and log off then back on which will fix it for a limited period. As the desktop is closing down I can see the programs I have tried to open starting up but as soon they are closed and I log off, then I log on again, same as before and everything works again for a time, I might have to repeat this two or three times a day. I wonder if anyone can help me....much obliged
I cannot remember if I upgraded anything or not when this fist happened, but the problem is beginning to escalate.

bosshogg