System locks up after Office 2000 & Expl

I’m running Win 98 and recently installed Office 2000. Since the Installation my system locks up while using the Internet. It Doesn’t matter which browser I use, Netscape or Explorer 5.0. When it locks up It prevents me from accessing my hard drive or any other items whether by desktop short cut or “My computer icon.” This never happened before I installed Office 2000 with Explorer 5.0

I was using Explorer 4.1 with no problems, but now have these problems poping up! Moreover, I can’t access my web based e-mail accounts through Explorer 5.0. I can access through Netscape 4.61.