Shopping cart images and full width problems

I am having a few issues with my website that I hope you can help me fix:

1. The product images in my shopping cart are tiny. I can barely make out any details when I go to the checkout. How can I make those big enough to see the text?
2. I would really like two areas at the lower part of my homepage to be full width, but do not see how to do that. I have set the column width to full width, but it still does not change the images. It is the white area that says Grab N’ Go or Design Your Own. Also, the blue area that says Order Today, Get it in 48 Hours.
3. If you click on “Banners-Customized” from the Product Categories on the left, you see the images of the products in that category. All of my product images in all categories are cropped. Is there a way to have the entire image showing without it being cropped? I have changed the sizes in the WooCommerce and run the Regenerate Thumbnails plugin, but the images have not changed.

Thank you for all of your help!