You can get the nmr spectra of your calculated nmr from gauss view. open .log file by gauss view then go to results, there you will find option for nmr.
To assign the peaks, you check the electron density on each carbon which can be obtained from .log file.
Please, find in attachment a very recent and excellent book on spectroscopy. It may be good to help you to get the NMR interpretation of your 4 organic molecules.