Although it seems as an old thread, but I had a simillar problem.Originally Posted by codenamevirus
Once your system is started, try checking the IIS control panel. It will show if your site is running. If it doesn't try sarting it manualy, this should give you some sort of the eror message.
Although, most likely cause, as been said before, is that you've got something else listening on port 80. This usualy causes IIS to stop.
Check all your chating programs like ICQ or IP telephony programs like Skype, as they sometimes tend to listen to port 80 as a default setting.
Good luck