I may welll be overlooking something obvious as I've only started using After Effects, but when I create a new text box or import an image, they're both appearing as if they've been stretched vertically. Here's a screenshot to illustrate - the window on the rhs is Illustrator, and the window on the lhs is AE, showing the vertical stretch. All my settings in the character window appear to be normal, 100%.
Read up on pixel aspect ratios and how they are used in video and for that matter AE.
You are also using a CMYK image in AE. That is a big no no.
The fix is to always create your compositions using the Square pixel default presets. Don't go messing with the pixel aspect ratio settings in your composition. That will just foul everything up. Use the presets and learn about pixel aspect ratios.