They say new movie is a lot like first Star Wars (A New Hope). That movie was released in 1977, some twenty years before you were born. Star Wars was the shit back then, now is a bit dated. So if you want to feel a bit of what people felt almost 40 years ago, then just watch newest movie. It's probably not that groundbreaking but if it mimics original a little little bit, it should be more than fine consider that most modern movies that come out of Hollywood are utter crap.
As for prequels, they weren't that bad. Especially third (Revenge of the Sith). My main issue with prequels, apart from bland and badly executed story is character cast. Anakins role was given to some schmuck no one remembers today. Some scenes in those movies are very boring to watch, for me scene when they go to investigate clones takes the cake (think it was Attack of the Clones).
After all these years, standout thing about Star Wars for me is performance of Alec Guinness (Obi-Wan Kenobi). Apart from that, Star Wars movies are meant for children but those specific parts still hold some value for me personally.
At some point George Lucas figured out that franchise merchandise sell better than movie tickets, so he added certain toy like characters to series. Like Ewoks and Jar Jar Binks.