PC suddenly off and not starting

I installed daemon tools from a cd in my pc, after installation of daemon tools,I opened daemon tools and I was about to mount an iso game file,suddenly my pc off and it is not starting, then I switched off the power and switched on again to start my pc, but no use,it is not displaying anything,just black screen coming and the small red coloured processing signal light of cpu (red light which is located at top left of my cpu) is also very weak, I mean when I power on,for about 2-3 seconds it would be good, in dark red colour, then after it wil be in very light red colour! I cannot understand what happened to my pc, I request, please help me to solve this problem!

May be a power supply issue... unrelated to the Daemon Tools install. Slysoft's Virtual Clone drive is a good free alternative to Daemon Tools:
http://www.slysoft.com/en/virtual-clonedrive.html
after you get the PC running again

Sir my hearty thanks for your previous reply,
sir, when I start my pc,it loads windows and as it starts, in about 10-15 seconds it freezes and remains at same position without any movement! I waited for about 15 minutes but it freezed at same position! What is the problem sir, why it is happening? Please help me sir!

run the windows startup utility fixer from the Windows CD. it may give you some clues. That is if your computer turns on now.