Hello, I was trying to get a preview of a rendered scene and this message came up but I dont know why? "Warning, Obscuring the viewport during an open LG render may corrupt the final image"

If you're using the OpenGL render engine this just means don't do anything until the image is done rendering.  OpenGL won't open a render window until it's done.

Is there a difference between the other render options?

If you go to the Render Options you have the choice of using hardware or software render engines.  I generally use the software engine because OpenGL isn't fully supported by DAZ Studio.  Just set the slider all the way to the right and you'll be able to watch your render as it happens.

Figured it out thank you for your help :D

My pleasure -

Open GL is just a "preview" mode.  It won't be any better of a render than what you see in your preview window....well, the gridlines will be gone, that's about it.  I recommend using the 3Delight renderer (the software renderer) to get better results from your render ;)

I have never had any problems with anything corrupting any openGL previews here. I can start the render and immediately open another window on top of Daz blocking it completely out. When my render finishes, I go to the file and it is fine. I have just ignored this message from day 1 and never in 4 years had a problem obscuring any openGL renders.