BleepingComputer.com: can not boot computer running windows vista home premium

I am working on my sisters compaq computer running vista home premium, they had contracted some viruses(trogans Etc.). was finally able to boot to safe mode and was able to run malware bytes anti malware program that was already installed, but was 180 days old on the definitions. tried to access the internet to update but would not access it it would only show a local connection. rebooted again to make sure i selected safe mode with networking, but still no internet. i used a jump drive on another computer and downloaded avast anti-vrus program, and was able to load it on the computer and ran the program. after running the malware bytes program it found like 10 trogans, i think. and the avast program found a couple of things as well. there were a couple of times that while trying to reboot in the normal mode, the computer would bring the normal desktop up for about 10 seconds and then it would go away and now all i get in normal mode is it gets to the welcome screen and while booting it just halts and the hard drive light stops blinking. I have tried removing the memory sticks one at a time and try to reboot and to no luck. replaced the memeory. all plugs and cables are plugged in and haven't seen any abnormalities on the motherboard. i have tried to use a start up disk from xp but that doesn't work either. I even bought a program from walmart that was called System Mechanic, and i can not get it to load up either. The system recovery is on the d drive partition but when trying to access it in safe mode it acts like there is nothing there. cAN ANYONE HELP? PLEASE ADVISE!

With the information you have provided I believe you will need help from the malware removal team.
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Good luck and be patient. Help is on the way!