Development Discussion Board

The manual of phpbb was clear enough for me to learn php.
http://www.php.net/manual/en/index.php

Something you could do to protect your own board is adding a protection that the other 'normal' boards do not have. It can be a very simpel question for example. Spammers don't have time to crack the protection for just your board.

You are right PHP does support UTF8

But not all databases have UTF8 as default character set. (MySQL for example has default latin1_general_ci as default) So it is possible that you have to change the characterset to UTF8 yourself to make it possible.

I don't think so, because PHP does not support it.

The default skin has valid XHTML 1.0 Transitional. But you could always check yourself:
Validate