Well, I can certainly relate to turning wrenches and coaxing more hp from an engine.
You certainly don't have to become a web-coding guru to be an effective vBulletin administrator, but I do suggest learning the basics of HTML/CSS...you will find just knowing this will allow you to figure out how to do lots of useful things on your site.
I have helped a bit on a vB 5 site, so if you want, set up a temporary admin account at your site and shoot me a PM with the login credentials , and I will be glad to come over and see if I can address some of these issues.