s**t, that's odd! You do have a problem in there! I've just tried it with Mozilla 1.1 and all I saw was the source page.
When I type in http://www.hostbet.com/index.htm (without the l at the end) I'm getting the 404 page in all its full colour glory. If I then click on any of the links (all seem to have the html extension), again the source comes up.
Conclusion: htm files are showing up, html ones are not.
That's weird. This may sound daft, but why not try adding this to your httpd.conf:
AddType text/html .html
stop/start apache and see if it makes the problem disappear.