Hi! I'm relatively new to speed running Silent Hill. I have an original Playstation and the Japanese version of Silent Hill. I've seen Aaron's WR and attempted to follow it as I play. At some point he's getting tackled into some stairs. Then after he's walking through a door to eventually land down in some other area. I know that the japanese version can softlock with the blood trick at the end. Can I perform the "IDCLIP" / NoClip trick with the japanese version?

Yes, there's two Japanese versions: 1.0 and 1.1

All versions can do the Antique Shop out of bounds (it was only discovered like 2 years ago).

The Aglaophatis Glitch (aka Amusement Park skip) will only work on Japanese 1.0 version, otherwise you will get the typical "Can't use this here".

It's easy to tell which version you have by looking at the disc, 1.1 has "Konami THE BEST" on it:

Thanks! I managed to do the Aglaophatis and the ASOoB glitch! Except been cheaper, is there any advantage to speedrun on Japanese 1.0 version? I can't remember how I softlock the game with the Aglaophatis glitch. That was a while ago. Maybe it has something to do with me letting the cutscene play until the end. Or my brain making false memories.

There is no known benefit, the IGT pauses while text scrolls so there's no difference between languages and there's no exclusive glitches that we know about.

And yes that cutscene can freeze the game if you let it play, seems to only happen on PS1/2 though (non emulated platforms).