The NTSC-US version is the original game, released primarily in the United States of America and Canada. The PAL version, released in Europe and a few other territories some time later, features a few tweaks and changes not present in the original game. Those are as follows:
Ripper Roo - Ripper Roo jumps slower in the PAL version.
The Lost City - At the very beginning of the level, two Crates can be found behind an Iron Box stack (3 boxes high). In the PAL version, it's actually possible to jump over it from the right (but not from the left), which is a bit of an odd thing to begin with, since Crash can usually jump over 2 boxes tops. This isn't possible at all in the NTSC version (or the Japanese one for that matter).
The Lab Checkpoints (by Brandon) - The PAL version only has one Checkpoint in the entire level, instead of the original two.
This is the Japanese version of the game and it's based on the original NTSC-US game, so none of the PAL changes apply to it. Lots of other changes were made to it, though.
(Credit goes to Micster for the following pictures.)
Title ScreenSaving - The password system was removed, leaving you only with the option of saving. The game remembers the Crash 1 slot after you save the game, this time around.
Fonts - Some text fonts are brand new.
Voice cast/text - The voice cast is composed of Japanese seyus, with Crash actually speaking and saying things more often. The text has all been translated into hiragana. These two changes remain consistent for the rest of the Japanese versions of the games.
(Video by Keiji Dragon)
Music - Some of the music is completely new. The levels that have new music are:
- Tawna bonuses.
- Koala Kong.
- Pinstripe Potoroo.
- Dr. Nitrus Brio.
- Dr. Neo Cortex (the Cortex bonuses, however, retain the original music).
Islands - To rotate the islands, you need to press L1 and R1, as opposed to Square and Circle.

Ore wa Aku Aku - The witch doctor gives you preset text hints when you collect certain masks. This trait remains in Crash 2, 3 and The Wrath of Cortex, although he has a voice in the sequels.
First Aku Box - Because you automatically start with an Aku Aku mask in the first level, the first Aku Aku box isn't there.

TNTs - TNT Crates have a bomb symbol instead of the word "TNT" on the sides. This change applies to all the other Japanese versions of the series.


Tawna - Tawna disappears from her bonus levels once Crash reaches her.

Box Count - Even if you lose a life in a level, you are still presented with the box count screen. Additionally, Crash is only hit by a single Crate, regardless of how many of them you've missed. The number of Crates you've missed is shown in the bottom line.

Papu Papu - The fat man is harder to beat in this version. Not only does he have 5 hit points instead of 3, but he also starts swinging his club faster and faster after the third hit.
Level Order - Sunset Vista and Slippery Climb were switched with each other. This was likely done due to Sunset Vista's tremendous difficulty spike, so here it ends up appearing much later in the game. The key to Whole Hog is still found in Sunset Vista, despite its new location.
Coloured Gems - Some coloured Gems have been switched around for better flow.