Of the movies I’ve seen that have influenced me the most, there is the original Star Wars movies, and there is Hayao Miyazaki’s Nausicaa of the Valley of the Wind. The soundtrack is by Joe Hisaishi and seeing him conduct an orchestra playing themes from that movie is just sublime.
YouTube – Joe Hisaishi – Nausicaa of the Valley Wind (Part1 of 9). <- link is much higher quality video than embedded one below.