As Rob said, begin with HTML and CSS, then if you decide that you want to really get creative with your site and make your jokes dynamically generated from a database you can add PHP and MySQL, not really needed up front in the beginning but adds to your abilities once you learn page structure and design.
Learning web development is a very rewarding career, if that is what interests you. It can be a lot of fun and give you a lot of challenges as you learn to develop and design web pages and web sites.
Or you could go the route Ron talked about and generate your site using WordPress, Joomla or one of the other out of the box systems. If that is more what you think you would like, but keep in mind that an out of the box CMS like WordPress has its own learning curve, and depending upon what you want to do that learning curve can be quite steep. Also you never have full control of your code using one of those systems as there are portions of those systems in the way that they are designed that are very difficult to modify, and they have security issues and are slow. That just goes with their popularity.
Start with HTML then move into CSS. I have a ton of free videos, well over 200 hundred, on my site that can get you started if you are really interested and if you have any questions just drop me an email from the site.
OnTargetHTML5 Video Tutorials
Good luck and have fun...