How i switch from internet explorer 9 to an older version?10 POINTS?

IE 9 doe sn t work with the new flash player version so,i was forced to use replace it with firefox even i didn t like the idea.Now after Only 2 days of use with firefox,i notice a lot of virus, and the worse,they didn t encrypt my passwords and Personal information,so my accounts have been all compromised..so i want to leave this **** cos i m very disappointed,and to go back to IE cos there i have no problem..so How i instal the older version?I GIVE 10 POINTS TO WHO CAN HELP ME INTO THIS ISSUE!! THANK U please explain step by step!