Bloody Bizarre Bug (spoiler)

[QuenGalad]

So, my man and I have decided to blow the dust off our Icewind Dale copy. We've installed it on his computer, we're sharing it to play right now, and I'm getting a bug he doesn't. Sometimes, my characters can't initiate dialogue. It' like being under a silence spell, only they aren't. Usually, coming back later helps. This is not a huge problem, so I just ignore it, but my man has nothing of the sort with his party. I'm writing that because it may be, in some mysterious way, important for the other thing.

At Dragon's Eye dungeons, I found the Lizardmen King. I was scouting ahead with my fighter/thief hidden, and came upon that big band of lizards, one of them blue-circled. I did not, at first, realize, that the others had green circles instead of red around them. Pretty weird, I thought, but no matter. The thief went back rather quickly, before he failed to hide, and I ordered a rest to heal before the fight. There was going to be the fight, right? What else could it be?
So after the rest, I selected all of them using the button in the corner of the screen. I think that is what caused, well, all the lizardmen from the cave ahead, save for the king, to come down to my party, and, um, stand there, still green-circled. The shamen cast some spells, some of them offensive, but the fighters did not attack. After a while I selected one of the lizardmen and found I can control him. All of them, in fact. So I selected everybody and went to the king, thinking that a dialogue with him would correct things. It didn't. He went hostile, and I litterally mobbed him to death with his own guards. Only when he died did the others finally fight.

The game is unmodded, the cheats are disabled, no fixpacks or patches yet.

[dragon wench]

I'd definitely suggest patching the game.
You can find the last official patch (which includes Trials of the Luremaster) [url="http://www.download.com/3001-7539_4-10236599.html"]here[/url].
Note, you need to have Heart of Winter Installed for this particular patch/expansion.

You can find the patch for the vanilla IWD (without HoW installed) [url="http://www.download.com/Icewind-Dale-1-06-patch/3000-7539_4-10236591.html"]on this page.[/url]

Other than that, I have no idea what it could be, especially since your man is not having the same problems. Maybe you somehow have a corrupted save???