On my website bbhydraulics.com it does show the menu in internet explorer.
here is the top part where I think the problem is:
<?xml version="1.0">
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html lang="en" xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
Is that the right code?