Wow, what a lot of questions.

So anamorphic widescreen, as far as DVDs go, means that it's sending out a 4:3 signal, but it's squashed laterally, just like a 35mm film, and the TV widens it back out, like the lens on a film projector.

Yes, precisely. "Anamorphic" in DVD terms is exactly the same thing as it's used in the movie industry. If I understand the way it works correctly, the telecine transfer of an anamorphic movie to an anamorphic DVD is a 1:1 shot. So the DVD player or the TV is tasked with doing the re-distortion at playback time, in much the same way as the anamorphic lens on the film projector makes the movie the correct shape at playback time. Interesting, huh?

I think that the reason some DVDs are letterbox-widescreen instead of anamorphic-widescreen is because the publisher just went the "cheap" route and dumped the widescreen VHS videotape master onto a DVD instead of doing a proper anamorphic remaster. What a waste!

Cool! Is that signal going to be an NTSC signal?

Yes, if it's played on a US DVD player. If it's on a european DVD player, it'll be a PAL signal.

Can I check my current DVDs to see if they'll play on my current TV as fullscreen-squashed to verify that they're anamorphic?

Yes. Simply go into your DVD player's configuration menus (the menu for the PLAYER ITSELF not the features of a given DVD movie), and tell the DVD player that you own a widescreen television. Then imagine watching the DVDs with the 4:3 image stretched to 16:9.

4:3 titles will still look right. Widescreen letterbox titles will look like normal letterbox movies. Anamorphic titles will be squashed.

Also, you can look at the fine print on the box of the DVD and look for the words "anamorphic" or "enhanced for widescreen TVs" to see if the title is anamorphic. Note that some boxes are misprinted. For example, my copy of "2010" is labeled as enchanced, but it is not. Made me really mad when I got home!

I've seen in the shops around here HDTVs that are 4:3 as well as ones that are 16:9. Is a 4:3 HDTV a bad idea?

HD is by definition a 16:9 screen, just like NTSC is by definition a 4:3 screen. So if you watch an HD broadcast on an HD-capable 4:3 TV set, it'll letterbox it for you.

Personally, I like having the extra size of my 16:9 television with which to watch the HD broadcasts. The extra resolution is really worth blowing up so you can see all of it. It ends up looking like 35mm film projected. Shrinking it down to tube-TV size is fine, if you're already used to watching letterboxed widescreen movies.

Something you need to keep in mind though. Even the HD broadcasters don't have enough material to fill their entire broadcast day with HD. For instance, the one station which shows the most true HD material is HBO right now. And only about 50 percent of their broadcast day is 16:9. The rest of it is 4:3 upconverted and side-boxed into the 16:9 HD frame. So on a 4:3 HDTV, you will get certain portitions of the broadcast day as a 4:3 postage-stamp in the middle of the screen if you're tuned to the HD channel. BUT if that's the case it's easy to change channels to the standard-def version of the same channel (regular HBO for instance) and have it fill the screen.

And is the 1080i the highest resolution thats out these days,

1080p is the highest resolution available for HD, but I've never seen a TV that'll do it.

The HD resolutions are:
- 540 progressive
- 720 progressive
- 1080 interlaced
- 1080 progressive

There is also:
- 480 interlaced (NTSC)
- 480 progressive (progressive-scan DVD).

Most HDTV sets on the market today will do 480i and 480p for TV and DVDs, and will do 540p and 1080i for highdef.

Note that each "p" mode requires twice the scan frequency, so for instance 1080i and 540p are essentially the same "mode" to many TV sets.

and will TVs that claim they do that also do the other HDTV resolutions?

NO. For instance, most current HDTVs will NOT do 720 progressive.

This is not to worry, though, as your HD receiver (whichever one you get) will have a mode switch that tells it to always use 1080i. In that case, it will upconvert a 720p broadcast into 1080i as necessary to properly send to your television.

I think the recent HBO Bruce Springsteen concert was this way (720p upconverted to 1080i) as I could see jaggies on high-contrast diagonals despite a very sharp and obviously high-def picture on the screen.