What you have done by setting your Windows scaling at 125% (to make everything bigger for your own comfort) is you have designed the graphics and formatted your page text sizes so that the text is readable for you *at that scaling*. Because the majority of people viewing your site will be doing so at normal 96dpi 100% this results in very tiny and hard to read text for normal people. (see my screenshot in other post)
The navbars are exported as bitmap buttons so they will never be as sharp as when viewing in the Xara design window as they are still vector fonts.
My advice is to always design websites with your screen set at 96dpi (100% Windows scaling) becuase this is how most people will be viewing it..

For now, I'd certainly reconsider the button colour and text size. Even the body text size would be better larger given the amount there is which you are asking people to read.