Thanks for the help. For what it's worth I had to add the following line to my .htaccess file:

AddHandler server-parsed .html .htm

I believe this instructs the server to look for includes in .htm and .html files. At least that's the way I understand it. I've messed with html/css for quite some time off and on (which means I'm still not very good at it) but everything past that is quite new to me.

It sounds like to me that the includes will do everything I want for the time being but I think in my spare time I'll try learning about PHP as well. Thanks again for the help.