I think there are three things that are catching you out here.
Firstly, the warning in Outlook. There are a number of Outlook Express
specific viruses around, and it seems you are being warned about one
of those. Normally you are given options about how to deal with it.
The include deleting it, trying to repair it or ignoring it. The best
course, especially for email messages, is to delete it. Better safe
The second part the URL - the web address you have included in your
question is an invalid one. It may be that the place you are getting
the link from has made a mistake, or you could have copied it wrong.
Most likely it was pointing you at Lavasoft, a company that
specialises in making anti-spyware software. The are located at:
http://www.lavasoftusa.com/ and the page you may have been trying to
reach is: http://www.lavasoftusa.com/support/download/
The third part is about the the Internet Explorer problem. Obviously
Internet Explorer is still there, as it's what you use to get to
websites (including this one). However with various configuration
changes it can behave differently. What you may have experienced is an
automated search that can occur when the website you try to visit
doesn't exist. This doesn't mean that Internet Explorer is unreachable
or anything like that.
However, if you would like to restore the Internet Explorer homepage
to it's default, you can do the following. When Internet Explorer is
open (on any website) click on the "Tools" menu at the top, and select
"Internet Options". Under the options window that comes up, you will
see a "Home page" setting - to restore it, simply click "Use Default"
then click the "OK" button at the bottom of the window.
I hope this helps. Let me know if I need to clarify any of this, or if
I misunderstood anything.