I remember being on one for Harry Potter and the Half-Blood Prince.

Also, nice reference! :D Hmm, let's decipher the GRM part!

At least they got rid of Waru. ^_^

hS

Since you already know the big twist, there's really no reason to go with Machete Order. So I'd say start from Episode I - that's the intended order. Y'see, there's this thing called ring composition, which really only works if you start at the beginning.
And, really, the prequels aren't as bad as fandom makes them out to be. Especially with the Jar Jar theory to watch them for.

It's a suggested watching order from a Star Wars superfan. Most fans will tell you to only watch the original trilogy, or if you must watch the prequels, watch them afterwards, and then go back to the first three to cleanse your pallet. However, like them or not, the prequels do have an impact on the story now, a rather important impact. So, the man on the internet known as Machete decided on this order:

IV, V, II, III, VI

He gives a very in-depth, nerdy reason to watch in this order, which you can read here. However, if you don't want to read the full dissection on why this order gives depth and importance to an otherwise bland-at-best prequel trilogy, then here are the reasons he gives to not watch in episode or release order:

"The problem with Episode Order is that it ruins the surprise that Vader is Luke's father. If you think that this reveal doesn't matter since it's common knowledge, I suggest you watch the looks on these kids' faces. This reveal is one of the most shocking in film history, and if a newcomer to the series has managed to avoid having it spoiled for them, watching the films in Episode Order would be like watching the ending of The Sixth Sense first.

"The other problem with Episode Order is that the prequels don't really have a story. They're just background for the real story, which is Luke's attempt to destroy the Empire and save his father. Watching 3 films of backstory is boring if you've never seen the films they're the background to. Hell, that's why George Lucas made Star Wars (later renamed A New Hope) first - it was the most interesting story he had in his brain at the time. Starting someone off with Episode I is a surefire way to ensure they don't make it through the entire franchise.

"Unfortunately, Release Order is also an instant failure, and the reason is a single shot. If you're watching the official releases and you view the original trilogy first, then after the Empire is destroyed and everyone is celebrating, Luke looks over at his mentors, Ben Kenobi and Yoda, and suddenly they are joined by... some random creepy looking teenager who needs a haircut. Placing Hayden Christensen in the ending of Jedi, since he's not in ANY of the other films, turns an ending that should be celebratory into one that is confusing for the viewer. The fact that Christensen looks like he's undressing someone with his eyes doesn't help."

As for where to start: Episode IV. Watch them in the order they came out like everyone else did. At least for your first time. After that you can pretend the prequels didn't happen.

He tried to make Star Trek into Star Wars, so now that he has the genuine article, he should be able to thrive.