about OPT

I am graduating soon and faced two choices:

1. applying for OPT, or 2. Getting a marriage green card. 

Although I could get married with my boyfriend for the green card, we both would prefer some time to prepare for a wedding etc. And within the one year period of OPT, I will get the marriage based greencard. 

Therefore, the choice would depend on how much an advantage would greencard bring me comparing to the OPT? Can anyone advise me if OPT would have a great impact on job application? 

Thank you very much for any insight.