The 'Exit' button being cut off in the main menu is easy enough to work around (Alt-F4 or down arrow then Enter). The text quality... not so much.
Is the text also blurry in full screen or windowed mode? Did you try another 64:27 resolution, like 1280x540?
Did you try disabling anti-aliasing, to see if that would make a difference? (though I'm not sure if any post processing effects are applied to text)
