DVD will work in USA?

Only if the DVD player in the US is "region-free" which it very well may not be. I learned this the hard way about 20 years ago.

Look up the specs for your DVD player.

If it's NTSC, that's North American standards. It also says "all regions" so it isn't limited to any particular region. Should be fine, as long as your player plays DVD9 format, which it should do, unless it's really ancient possibly.

Agreed. "All regions" should be "region free". But they are not the same words and some weasel might have twisted them.

But yes, it's a good bet.

The DVD standard seems to be up to DVD10. Don't know how recent DVD9 is but you might need a newer DVD player. But it won't be locked to a region.

https://en.wikipedia.org/wiki/DVD

DVD compatibility usually comes down to region codes and the player, not the country itself. Most US players are Region 1, so Region 2 European DVDs won’t play unless the player is region-free. I’ve traveled with discs before and the easiest fix was a cheap region-free player. TVs don’t matter here, it’s all about what the DVD drive allows.

Some time ago I read that DVD players designed for use with iMacs would play foreign DVDs. I have not done any research on the topic. It's possible that information is incorrect, or that it used to be true but no longer is.

I bought a cheap DVD that I could reprogram to play European regional disc. Your regularly American DvD won’t play this.

The DVD will probably be region free. The way the system works is the the publisher of a DVD can decide where a DVD will be playable. Each player is supposed to be set to a region (but there are ways around that) and is supposed to refuse to play DVDs that the publisher has not permitted to be played.

This is mostly used by movie studies who want to control when movies are released in different markets. I have known how to get around that for decades btw. :-)

It is logical that a company selling DVDs to foreign tourists will code them so that they play everywhere. So I would assume they do. Myself I do not buy DVDs anymore, and on the occasion that someone sends one to me I immediately copy it to my media server. Our household does not even have a TV anymore...

Region-free DVD players definitely do exist (and are certainly not illegal). I've had one since 2009 that still (mostly) works, although it is used very rarely these days.

I bought a "region free" portable DVD machine from Amazon. They're around.

When I bought my Oppo DVD player, highly specked for a home theatre set up, I bought an optional "region free" card. This was inserted into the machine by opening it up and slotted into a bay that was built in to take it.
This was probably about 15-18 years ago. I haven't used DVDs for at least 10 years. You could possibly get the same thing from YouTube or at least something comparable. If into tech, YouTube also has 4K Ultra HD videos and VR tours, but you need the special goggles.