Yisro

When Yisro heard about the miraculous escape of the Jewish people from the land of Egypt, he took Moshe's wife & two sons & went with them to the desert to join the Jewish people.

The posuk first tells us וישמע יתרו , that Yisro heard, which Rashi explains as him hearing about the splitting of the sea & the war with Amalaik.  
The 'זוהר הק questions, was it only Yisro that heard? The whole world heard!

Chazal explains that, indeed, everyone heard the same thing, but what did Yisro hear that would cause him to uproot himself, leave all his family & possessions behind to go join the Jews in the desert? He must have heard something extremely special which only he was privy to. What did he hear exclusively?

They answer is that he heard what everybody else heard. However, the world heard & it just gave them momentary pause. Then they went back to regular life. Yisro heard more than just the words because he did something about it, he acted on it & changed his life.  

While that is certainly commendable, how does that get him the merit to have one of the most fundamental parshios in the Torah, one with the Ten Commandments in it, named after him. Wouldn't it have been more appropriate to name it after Moshe who brought us the Torah?

The sefer זכרון אליעזר explains that later on the Torah tells us that the Jews traveled from Refidim & went to the Sinai desert.
Rashi explains why it has to tell us that they left from Refidim. We knew that they were camped in Refidim, so, naturally, that’s where they left from. He says it’s to tell us that, just as when they came to Sinai, it was in a state of teshuva, repentance, so too when they left Refidim, it was in a state of Teshuva.

Why does it need to tell us that they left in a state of teshuva? As long as when they got to Sinai they were in the state of teshuva. Why does it matter how they were when they left?

Rav Tzudok says that there are two parts to Teshuva. One is to remove yourself from the bad & the second is to do good to keep you away. So, continues זכרון אליעזר, perhaps by receiving the Torah they had to remove themselves from bad which was the teshuva when they left Refidim & then they had to do good which was the teshuva going into Sinai.

With this understanding, we can appreciate why the parsha is named after Yisro. The main part of this parsha deals with the acceptance of the Torah & the preparation for it. One must renew oneself to be able to serve Hashem & not focus on any past sin but rather to strengthen oneself for the future. That's why the parsha is named after Yisro. As the posuk says ויבא יתרו.... אל המדבר , that Yisro came to the desert. Rashi clarifies that it needs to tell us that Yisro went to the desert to teach us his greatness. Even though he was a minister in Midian & on top of the world, he gave it all up to go join the Jews & live in the desert in order to hear the words of the Torah.

Someone like that who is willing to give up the past & only look to the future is worthy to have this fundamental parsha named after him. It teaches us to emulate him & not look at our past but rather resolve to better ourselves & then only look ahead!