To burn an ISO file you don’t need DVD Shrink.
To check if the ISO file is correctly edited, VLC player is a good test. Open the ISO with VLC, and if everything is good, then you can burn the ISO on a disc.
I don’t remember exactly where, but in nero there should be a menu with something like “Burn image”.
Alternatively, install ImgBurn (an excellent and free software), select the Write mode, then load the ISO file, insert a disc in the burner, select burning speed, and press the start button