Hi guys, I decided to play through this series and ran into a few issues that our modern PCs are having. I believe I've got it working on my computer fine now, so I thought I'd pass on what I've learnt:

Mods
Reshade: https://www.nexusmods.com/deadspace2/mods/26?tab=description
Unlock Conduit Rooms: https://www.nexusmods.com/deadspace2/mods/57?tab=description
These will make the game nicer and unlock some doors that were designed to unlock only if you have a save file for Dead Space: Ignition (Console only).
The Reshade preset requires you to install Reshade. Google it, download it, copy the reshade preset from the nexus to your game directory, install reshade to Dead Space 2, select the preset that you've already copied to game folder (might even be automatically selected if you're lucky), and then uncheck the optional effects during the reshade installation (2nd checkbox).

Nvidia Control Panel Changes
Vsync: ON
FPS Limit: 60

In-game settings
I maxed the graphics and disabled Vsync.

Fix for flickering and CTD on Launch:
Source: https://www.reddit.com/r/DeadSpace/comments/y3kxrl/does_anyone_know_how_to_fix_this_texture/
Basically you need to patch the game to limit the CPUs.
You download this tool:
https://learn.microsoft.com/en-us/windows-hardware/get-started/adk-install
And do this (Copy Pasted from the source link in case that goes down, but 100% credit to u/__0xi ):

Автор сообщения: u/__0xi

Alright looks like I found a fix that doesn't rely on DXWrapper and doesn't cause any weird ♥♥♥♥ to happen. You just need to install Microsoft's Compatibility Administrator, you get that here by installing Windows ADK (Assessment and Deployment Kit). When you install Windows ADK it gives multiple options you can select for different tools, the only one you need to select is Compatibility Administrator.

1. Launch the 32-bit version and select the new database under custom databases
2. Click the database menu > Create New > Application Fix
3. Provide the full path of the DS2 exe and give it whatever name
4. Skip past the compatibility mode options
5. In compatibility fixes select "ProcessorCountLieForHybridCPU"

There is a test run option you can click to attempt launching the game before you actually save the fix to see if it works, but after you save the database you will need to click install from the file menu. After you install the database it will automatically apply this fix each time you launch the game.

Only Issue I have is booting the game takes a couple minutes. Pretty sure it's reshade doing this, but I tend to have long gaming sessions so it's gonna take me less than 10 boots to finish the game easy.

No credit at all to me for any of this. I merely stand upon the shoulders of greatness.

P.S.
Unrelated, but just in case you're running your mouse using factory defaults:
Consider lowering sensitivity in games as much as possible and then going into your mouse settings and bringing up the DPI until mouse movement feels normal again. It does mean that you'll need to tweak this for most games you play, and even in windows, but you'll end up with silky smooth mouse movement in games, especially at higher res. Default Windows software doesn't seem to allow you to adjust DPI, so you'll probably want to use the software from Logitech, Razer, or whatever company made your mouse to do this.