1a) Everything language has good things and bad things. I like HTML because it's easy and I've learned it well, so it's hard to get away from it. PHP though is very dynamic, so if you think you can learn anything... PHP would be a good choice... it's also in some areas similar to HTML.

2a) For "easy" management you have two choices. You can either use something like FrontPage, Dreamweaver, etc to create the website. It will be easy to manage BUT only on the computer you created it... unless of course you transfer all the files to another computer. Another way would be a CONTENT MANAGEMENT SYSTEM (CMS) which would allow you to change things easily as well, AND you can change them anywhere you like, because it's WEB BASED, which means you login to your website and make necessary changes directly online. The down fall is that if you make a mistake, the website is messed up- whereas if you do it locally with a software, you can always UNDO an action or download the working version from your webhost. Then again, most webhosts have BACK UPS... which they might do once a week, once a month or even every day. The good thing about the CMS is that ANYBODY ANYTIME ANYWHERE (w/ an internet connection) can change is if they have access.

2b) That is possible with a CMS.

3c) Well, if it's not going to be linked to some kind of game where it updates automatically, you can use maybe even the CMS to do that with the correct plug in or you can use something like CORANTO, which is a very simple version of a CMS, but because it's so simple you can do whatever your heart desires. It's easy to setup you can easily add/change points which will then automatically update to members profiles.

3d) I don't know how many memebers there are, but you could it like: they register on the site... or actually, the people who will be working with you on this, you can create their account, and then you can also create them an account on the forum, or simply have them register where you have to approve and you just match the registration to the account on the website.

If you need help or have questions, let me know.