Here's the situation and problem:
My computer: Dell Dimension E510, 2MB RAM, 3.2GHz CPU, XP Media Center Edition, Version 2002, Service Pack 2, Easy Media Creator 8 Suite.

For the last several years I have been making home movies for my children and grandchildren as a Christmas present. I’ve been using Slideshow Assistant, VideoWave and MyDVD. There have been occasional problems with Videowave crashing, but I have always - with patience - been able to get the job done. So I'm doing the same thing now. In fact, I have already created one of the DVDs for this year, but am still working on the rest.
My usual procedure is to create the mpg movie with VideoWave and then to check it by viewing it in Media Player.
The trouble started a few days ago when I tried to check a recently made movie. I double click on the movie and Windows Media Player opens and then produces an error window, saying it is unable to run the movie. I went back to Roxio and recreated the movie. Same results. I then tried playing an mpg movie made last year, but got the same error.
Then it gets worse - I think.

Thinking that the problem is somehow with the Media Player software, I burned a DVD with this problematic mpg, as well as a few others that had previously run fine in Media Player. I loaded the DVD into my Panasonic DVD player and got an error message that it was a bad disk.

I have uninstalled and reinstalled Easy Media Creator 8 Suite. The results are the same. I can view the production in VideoWave. I can preview it in MyDVD. I can’t view an individual mpg file in Media Player and when I burn a disk, I can’t get it to play on my DVD player that is connected to my TV, nor on my computer. I have tried using Dell CinePlayer and Dell Media Center. Both tell me there is a bad disk – and I’ve burned new disks several times, so it wasn’t a bad disk.
Can someone suggest a (free) mpg player so that I can at least check if the files are corrupt? I don’t think they are but ...
If an mpg file is corrupt and is burned to a DVD, what effect, if any, will that have on playing the DVD?
Any ideas? I’ll be most grateful.
Thanks.

If the mpg file is corrupt, I doubt that you'll be able to burn it to a disc using My DVD (orDVD Builder). You could probably burn it to a disc as a data disc but it will not play on a set top DVD player.

1) You can indeed get a bad bunch of discs so that several are defective. Try not to use Memorex or store brands. Verbatim and Taiyo Yuden (order on-line) are good to excellent.

2) Download and run Gspot. Add the video an it will tell you what kind it is and if you have the right codec for it. My guess is that something happened and the codec was corrupted.

3) Download and run VLC player. It will play just about anything.