i can read everything in your screen shot just fine, its actually close to the size of the font on my screen. maybe just use a smaller resolution if you cant see it all that well, as far as why ctrl + and - arent working beats me, ive never come across that problem, and i used to work at a PC repair shop, ive fixed close to 1k computers, never heard anything like this before honestly.
maybe you need glasses? i kid, but im tapped on ideas as to why its small and you cant adjust it