If you are new, I would suggest you try out MRIcroGL instead of MRIcron. Primary development shifted to MRIcroGL in 2011, so MRIcron has seen minimal changes in the last decade. The only disadvantage of MRIcroGL is that it requires a graphics card that supports OpenGL 2.1 or later (released in 2006):
  https://www.nitrc.org/plugins/mwiki/index.php/mricrogl:MainPage

It looks like your image is anisotropic and was not aligned with the scanner bore. The options on the top of the Preferences page allow you to determine how these issues are displayed. However, one typically normalizes these images to standard space and applies overlays to the normalized images (which are isotropic and resliced to be orthogonal with standard space). 

I highly recommend the FSL workshop for new users. However, all the Google slides and sample datasets for my class are available online:
 https://crnl.readthedocs.io/psyc589888/index.html