This thread was the first to pop when I was troubleshooting Legacy of Kain: Soul Reaver on Windows 98 SE. I was unable to find reliable solutions, so I hereby post mine in direct response to this topic.

Specs: nVIDIA FX5700; Driver 52.16; P4 1.7GHZ; ASUS P4P800-VM; Windows 98 SE

Problems:
• v1.0 and v1.2 game crashes on startup with “DDHELP caused an invalid page fault in module <unknown> at: …”
• Game crashes with a blue screen if you try having another ddraw process running (e.g., Media Player with video file loaded).
• The biggest problem that the game crashes entire PC on launch and it is annoying to troubleshoot restarting it each time.

My Solution:
• Update the game to v1.2 (official patch by Crystal Dynamics).
• Use Unofficial Soul Reaver Patch for XP and Vista (exe file contained there is meant for v1.2 specifically). (unofficial patch by The Lost Worlds)
• Set Windows Desktop to 640x480@16bpp;
• Set game resolution to the exact same 640x480@16bpp on launch.
• It should run.

Tried Other Solutions:
• DxWrapper (suggested by PCGamingWiki). Does not work on Windows 98.
• Running Media Player with a video loaded, as suggested on web, to make DDHELP happy. Goes further but produces bluescreen.
• Wrace Legacy of Kain Soul Reaver sr1patch (can be accessed using Wayback Machine via Nosgothica game’s fan page, the exact download link still available in Thelostworlds net). Does not work on Windows 98.
• Disabling HW acceleration. Crashes the PC in Software mode.
• Modified exe by scene group. Same as above.

Misc.:
The same DDHELP problem affects other games:
• Carmageddon 2: Carpocalypse Now (solution – use nglide wrapper).
• Nightmare Creatures (pc may crash on game exit with DDHELP error, setting desktop and game resolution to be the same might help; playing in software mode might help).