You need to go in the HikaShop options of your menu and change the "parent category" option to the category you want. You can easily access the hikashop options of your menu via the menu Display->Content menus.
In that same option screen, you have the option "associated modules" where you must have one products listing module which is published. If you unpublish it, you won't see it below your products listing.
There is no option to make the image clickable on the listing. However, it can be done if you modify the code of the file "listing_img_title" of the view "product" via the menu Display->Views. But you need to know php to do that.
Same for the images in the cart and the checkout (it's the file cart of the views product and checkout that you would have to edit). In next release, you will have the possibility to display the images on the checkout via an option.