Throughout the entire episode, the video frame was zoomed in and cropped for the dubbed version compared to the Japanese original. This change results in approximately a 10% loss in the overall video frame for this episode.

It is easily spotted in this scene on the left side near the top railing where the squiggle gets cut off.

The English dub called Ash's Taillow "stubborn" while the Japanese original called Satoshi's Subame "fiercely competitive (負けず嫌い)".

Narrator English Dub: As they traveled, Ash managed to capture a stubborn Taillow...
Narrator Japanese Translation: As he traveled on, Satoshi got a fiercely competitive Subame in the Touka Forest.
Narrator Japanese: その途中　サトシはトウカの森で負けず嫌いのスバメをゲット。

Masato in the Japanese original thinks the boy they just saw might have fought a legendary Pokémon but Max in the English dub thinks it might have been the Pokémon they saw on the sign moments ago.

You'd think the BIG picture of a Pelipper would make this part of the scene kind of pointless?! Who's that Pokémon?! Is it Mewtwo!?

Max: He must be talking about the one on that sign back there.
Masato: Could he have fought a legendary Pokémon?!
マサト: ひょっとして相手は　伝説のポケモン！？

Brock thinks that Anthony should hold seminars while Takeshi thought that Antony was being a bit too confidence. Very different opinions on the guy.

Brock: This guy should hold seminars.
Takeshi: He's confident to a fault.
タケシ: すごすぎる自信だな。

Takeshi continues to think that Antony was being a bit too over confident while Brock just thinks that that battle rules against Anthony just keep getting better.

Brock: Well, this just keeps getting better and better.
Takeshi: That confidence of his is outright blasphemous at this point.
タケシ: 神をも恐れぬ自信だ。

Jessie, albeit a few years earlier than the famous Shia LaBeouf Just Do It Motivational Speech, says they just need to think of a plan and "just do it". Musashi though says that "Doing things fair and square!" is not their thing and that they should just use their guile to get the world's strongest Pokémon.

Character	English	Translation	Japanese
Jessie	Hey!	Oh come on! We're the Rocket Gang!	もう！　アタシたちは　ロケット団よ！
Jessie	Let's remember who we are and just do it.	Our motto is "Doing things fair and square!"	正々堂々と！
Rockets	OK, we'll just do it!	Fair and square?!	正々堂々と！？
Jessie	Glad you see it my way.	"...is not our thing!"	やることないのよ！
Jessie	Now, put your heads together and come up with a plan.	With that in mind, let's use our guile.	そこんとこは悪知恵　働かせましょ。

Meowth says "Resistance is futile" in his first line when talking to Anthony. The phrase was made popular by the Star Trek The Next Generation character Locutus of Borg.

Meowth: Resistance is futile. Come out now.
Nyarth: Resistance is futile! Come out and surrender yourself!
ニャース: ムダな抵抗はやめておとなしく出てくるのニャー！

The Japanese original has each of the Rocket Gang members finishing the whole sentance about their defense measures while the English dub has the Team Rocket members each talk separately about their Poké-power-play plan.

Character	English	Translation	Japanese
Jessie	Activating Poké-power-play plan.	Our anti-world's strongest Pokémon...	対世界最強ポケモン用！
James	More powerful than Pelipper.	...total defense measures...	完全防御態勢！
Meowth	Don't get me started.	...are ready!	完了ニャ！

The Japanese original and English dub line for James is pretty much the same except for the addition of "poly-tech Pokémon" to the English dub dialog. This appears to be some kind of 4Kids made up description to make it seem like Pelipper is a fancy, rare and hi-tech Pokémon.

James: You had the nerve to fill Pelipper's beak with Pokéballs and parade it around like it's some sort of poly-tech Pokémon!
Kojiro: You put lots of monster balls in Pelipper's mouth and sent out a Pokémon every time!
コジロウ: ペリッパーの口の中に　いくつものモンスターボールを入れといて その都度　ポケモンを出してたってわけか！

Kojiro in the Japanese original makes it a point to tell Antony that they shouldn't mess with Musashi as she can get very moody and when she tells people to do something, they'd better do it otherwise they'd have to deal with her mood. James instead says Anthony needs to pay attention to them and Meowth calls Jessie conniving.

Character	English	Translation	Japanese
Jessie	We can help you out with that but you'll have to help us first.	If you don't want us to do that, kindly cooperate with us.	それがイヤなら　アタシたちに協力しなさい。
James	And you'd better pay attention, buster if you know what's good for you.	You better not oppose Musashi when she's in this mood!	こういうときのムサシには逆らわないほうがいいぞ！
Meowth	Because when she's conniving like this, don't mess around.	If she says she'll do something, you bet she'll go through with it!	やるといったら絶対　やるからニャ！

Nyarth quotes his famous Coins before cats phrase which the English dub changes.

Meowth: The sky's the limit.
Nyarth: Coins before cats!
ニャース: 「猫に小判」ニャ！

Kojiro tells Nyarth in the Japanese original that once they get Pikachu he'd get most the credit for capturing it. James in the English dub though just refers to his earlier statement that Meowth would be the Battle Director.

James: You know everybody wants to be a director.
Kojiro: Once we get Pikachu, you will get immense credit for it!
コジロウ: ピカチュウをゲットしたら　大手柄ですよ！

Nyarth in the Japanese original says his whiskers got fried from Buby's Flamethrower. Meowth doesn't specifically say that and just makes a general note to himself about fire safety.

Meowth: So that's why they say never play with fire.
Nyarth: Ouch, my whiskers got fried!
ニャース: ニャー　ヒゲが　焦げたのニャー。

The English dub completely rewrites what Haruka said in the Japanese original to make her seem like she's still learning about how nice it is to have Pokémon and being a Trainer.

May: Wow. This Pokémon stuff gets better all the time.
Haruka: Hm, I think you're getting a bit caught up in the exuberance of youth here, no?
ハルカ: う～ん　これってちょっと青春　してるかも。