if it's only starting in safe mode and not normal mode, it means one of the applications you set to run automaticallly on login is bugging out. start it in safe mode, then go to system preferences -> accounts -> login items and there will probably be one with a cross over it. click it then click the subtract (-) button to remove it from the startup list. In fact you can probably remove all the applications from there. then restart into normal mode and it should work