|You have to press F8 before the OS starts to load. (Your details weren't clear on that.) Once it starts loading--safe mode or otherwise--F8 has no affect.|
Is it always booting to safe mode on its own? If so, correctly use F8 to get the boot menu and try the option to boot to normal mode. If that doesn't work try 'last known good configuration'.
What happened to it between the last time it worked OK and the first time it didn't?