Ad-aware causing mysterious hardware failure/fry?

alright i just had the weirdest problem ever trying to rid my cousin's computer of some viruses. it's sorta similar to the thread where the guys computer wouldnt boot up/beep/ or whatever.

so i go down there taking the updated version of ad aware personal, along with the new definitions cause i knew there were many many spyware/adware/viruses on her computer. so i install it and run adaware and it finds like 69 registry entries, and i look at em all and theyre all like the sme thing but i cant remember what it was. so i remove all the them, and the taskbar disappears like when u get an explorer error, then ad aware says that it couldnt remove one entry and ask if i would like to remove on the next reboot and i click yes. . so i said well i'll just reboot and remove that file, so i hit restart and it acts like its restarting. i wait aminute the monitor kicks off to the standby patented orange light thing and nothing happens. so i just turned it off with the button on the comptuer. then i turn it back on and it does nothing

it acts as the its booting up but monitor stays in the standby thign with the orange light, no green light. no beeps, no nothing just sits there. i tested her monitor on my computer and it works normally, and i took my monitor down there to hers and it does the same thing, doesnt come on..
could somebody help me out, could it possibly be a hardware problem because i'm not too educated in that department and would prolly let her take it to repair tech if thats the problem. help me out guys i'm a deseperate beginner going into computer repair after highschool lol

Remove all unnecessaries to boot as usual and try CMOS clear or replace Lithium battery. Then boot from floppy only.

Describe all system environ. as usual.