Its been a while but hope that my response would be beneficial for others who may face the same issue as the author. If all of the above software and malware removal and cleaning wont work then you may want to check the integrity of your hard drive, delays and bad blocks can cause your system to boot up slowly. download speedfan [http://www.almico.com/speedfan.php]and install the software to check on your system temperature and SMART attribute of your drive, its very simple and easy to use, for details you can check :[http://www.almico.com/sfscreenshots.php] for details.