Giving Kedusha

Why does the parsha of Yisro precede that of Mattan Torah? Why was there a need for a great spectacle of sounds, lights etc. at Mattan Torah?  Why is there a need to remember the event of Mattan Torah according to the Ramban?  

The giving of the Torah was not a mere giving of national laws to a new nation.  It was a form of establishing kedusha in Klal Yisroel.  The purpose is וְאַתֶּ֧ם תִּהְיוּ־לִ֛י מַמְלֶ֥כֶת כֹּהֲנִ֖ים וְג֣וֹי קָד֑וֹשׁ.  The Or Hachayim already notes that the Torah records the story of Yisro before Mattan Torah to teach us that even though there may be very smart gentiles with innovative ideas such as Yisro, nonetheless they are not part of Klal Yisroel.  The nature of the great spectacle that was Mattan Torah was to establish the proper mood that is necessary for learning Torah in order for the kedushat haTorah to permeate through the individual.  As the Gemorah Berachot (22a) says מה להלן באימה וביראה וברתת ובזיע אף כאן באימה וביראה וברתת ובזיע.  Part of the studying of Torah is the necessity of the proper state of mind.  If the point was a pure study of information why is this a requirement?  Because it is not about a pure analysis of information but is rather a means of instilling proper kedusha in the individual.  That is why one must remember the event of Har Sinai to recall the meaning behind the study that one is doing.