You can download the newest version of Internet Explorer from http://www.microsoft.com/windows/internet-explorer/thank-you.aspx
Susan777, if IE 8 is giving you trouble, try running it with Add-ons disabled by going to the Start Menu, then All Programs > Accessories > System Tools > Internet Explorer (No Add-ons) . If it works fine, then you have a problem with an IE 8 Add-on or two. This post from the IE Blog will explain how to deal with this issue - http://blogs.msdn.com/ie/archive/2009/07/18/how-to-make-ie-open-new-tabs-faster.aspx
I hope this solves your problem!
MSFT Internet Explorer Outreach Team