The "Read This" section and the Episode Complete story text screens (paged book part) aren't being rendered with pixel aspect correction unlike the rest of the game.
Basically, the original game would render at 320*200, with a pixel aspect of 1:1.2 to fill a 4:3 ratio (compared to 320:240 with a 1:1 pixel aspect).
As those screens are aspect corrected * 1.2 vertically they currently appear vertically squashed, as the pictures in them are drawn to look correct with rectangular pixels.
This is fairly common in old dos games, although not all artists used to compensate for non-square pixels, to me it looks like Wolfenstein did (much like doom). Therefore in this case i think aspect correction of those screens is the "intended" look.
In fact, It looks like you are doing some pixel aspect correction already, since the ingame hud and graphics don't look squashed as far as i can tell (i haven't checked though).