When I'm sitting on the runway and looking out in the distance, I see lines that are moving, similar to heat waves on a summer day. Which setting should I work with to make it right. Thanks

Blurriness is caused by only one thing - high settings or settings which make it very difficult for your computer to render the texture fast enough.  If you lower the settings and let your computer "breath", perhaps the blurriness will go away. 

 

If you are seeing blurry textures "out in the distance", you can increase the level of detail by adjusting the first slider in the FSX settings (LOD Radius) but realize the further out your fsx is "looking", the more difficult it will be for your computer to render the textures.  It is also not very realistic to have clear and crisp textures "out in the distance".  Yes, down and around your aircraft but not in the distance.

 

Best regards,

If your problem is not blurry textures, but you get texture flickering (e.g. water, fences, building edges, signs, etc.), then try using the SGSS settings (lower number first) in Nvidia Inspector  (Anti Aliasing - Transparency Supersampling).   This will help to some degree, but you may take a hit on your frames.   I get by with 8x Supersampling, but do get some flickering, which is bearable.

 

Chris