[SixOfSpades]

True--all of the areas you mention have creatures using the GOLEM_LARGE avatar, and since you say that killing those creatures seemed to fix your problem, then it certainly sounds like a corrupted install, where not all of the animations for GOLEM_LARGE got saved correctly. To test this: Enable the CLUAConsole in your game (if you don't know how to do this, just ask), select one of your party members, and use CTRL-6 and CTRL-7 to cycle through the various creature avatars. If your computer suddenly has issues with GOLEM_LARGE, you've found your culprit, and I would suggest an uninstall & full reinstall, to try to get those animations copied correctly. If that fails, you could use Shadowkeeper to edit the files of all Iron/Adamantite/similar Golems, to make them use some avatar other than GOLEM_LARGE.

I doubt that mods, or any of your settings, are at issue here. None of the mods you list alters Golems in any way that I can recall, your 3D Acceleration and Sound settings would be affecting the entire game, and as for computation slowdown, you would need a hell of a lot of stuff to see any noticable lag. I've only experienced that once, in a mod battle that involved roughly 150 enemies, each with their own AI, charging at my party simultaneously. On a Duron 750 CPU running Windows ME, that caused nearly total freeze--your computer (whatever it is) should have no trouble at all with the first floor of Watcher's Keep.