Burnt data DVD freezes comp - wont run.

[TriFrog]

When I burn a DVD (I usually use Nero) when I go to play it it either freezes my whole computer, or it simply dosn't respond and I can't use/veiw any of the info on the DVD.
It includes all types off files: .avi .mpeg .mp3 .cbr .doc and so on. They are all in working condition on my computer before I burn them off.

At first when this happened, the dvd's were running fine on my computer. But I went and burnt a dvd data disk for a friend, and it wouldn't work on his computer. Curious, I also tried burning another dvd and opeining it up on my other computer. It did the same thing = It either does not respond when it opens up and it shuts down, or the whole computer freezes and I need to hard boot.
I decided to send the error report in to see what came up (Windows XP) and they said it might be due to something being wrong with the files. So I thought maybe there might be somekind of virus/spyware/bug on my computer that went undetected or somthing. So I reformated my computer.
After reformating, now the data on the dvds I burn wont even play on my computer anymore! This includes the old dvds I burnt and tried playing before reforating, and new dvds I burnt after reformating.
I'm thinking it might be my dvd burner, but I'm just not sure. Maybe it's the dvd's or some kind of incompatibility. I just dont want to run out and get a new DVD burner if that's not the case. I'm also thinking more likly it might have to due to a program incompatibility - Maybe the version of nero I use is not good to use with my OS? What should I use if so?

Also to note, I have also made a few backup copies of some video dvds I own on my computer. I use the same dvd's and CloneDVD2. Half the time the end of the dvd either freezes at points or skips a few minutes. The other part of the time things work out just fine.

Here's my stats:
Windows XP; 448 MB RAM; 149 GB (usually at least 30 GB free)
The DVD's I have are FujiFilm DVD+R (up to an 8X Write Speed)
I've tried a few versions of Nero
~The other computers the DVD's wont work on are also Windows XP

I thank you very much for any info or suggestions. =)

[Dv8ted2]

It could be bad discs, but there is no way of knowing for sure. What versions of nero did you use? If you try different discs, does the same thing happen? What model is your burner? Have you updated the firmware lately? Do you have DMA enabled on the burner?

Have you also cleaned the lens lately?

[Krispy Kritter]

In my experience, it is most likely a bad / failing dvd burner. Media could also be the problem.