You can do most of what you want out of the box or with some modifications. If you know HTML, even a little you have half the battle won. You can modify and change anything you want with phpBB but it's not a simple procedure where you can just use WYSIWG editor or web interface to do that. There is a learning curve.
phpBB doesn't have this but there are mods for it.
Forum & Message Board
,this is certainly covered.
Allow members to enter and edit their personal information,
There is a profile page for each member and memberlist, you can add custom profile fields so this is covered.
A page for remembering those who have passed away,
You could create a custom page for this, might even be mod you could uses or request one.
“Results! Why, man, I have gotten a lot of results! I have found several thousand things that won’t work.”
Attributed - Thomas Edison