NEC 3540A can't read burned DVDs, plz Help~

Hi all, I just found this great website and been reading posts for few minutes now.
Anyways, I have been using NEC 3540a for about 6 months and it’s been excellent DVD writer for me.
Last night I burned 2 DVD+R (16x Memorex brand) with NEC 3540a and it burned both of them without any problems.
BUt when I tried to play the movie files (i burned them DVD iso type and backed up some AVI files using Nero 6) the driver hangs and freezes the system.
The windows explorer read the DVD first time but if I refresh or try to click on the files on DVD, the whole system hangs/freezes.
If i eject the DVD, system comes back from hang/freeze.
I am running Raid0 and have X2 3800+ with Gigabyte K8N Pro-SLi mobo.
I just tested burned DVDs on my brother’s DVD drive and they read fine.
WHat could be the problem?
Please help me~~

p.s. one more thing, when it freezes, my HD light turns on stay turned on for weirdest reason. and please pardon my lack of computer knowledge as I am really not an expert like you guys :o

I did some testing on my own after reading some postings here. I uninstalled Nvidia Sata device and installed MS one but it didn’t fix my problem.
I can burn and read CDrom without any problems.
I can burn DVD but I just can’t read the burned DVD; it just hangs and freezes my computer. ( this is happening after winxp booted up )
Also I see the DVD driver on windows explorer and can see the files on burned DVD, BUT when I do refresh or try to copy the files from burned DVD to my HD, it hangs and freezes.
I am beginning to think that my 3540a is broken because I dont’ see any other problems except the laser gone bad so it can’t read DVD.
I have ran some burned DVDs on my comp and my brother’s. Oddly, my brother’s DVD driver can read these burned DVDs just fine but not on mine.

Did anyone have similar experience?
I’d really appreciate it if someone can give me some ideas or their opinions about my situation.
Thanks guys and please please help me~~

Update Nero first to 6.6.0.18, IIRC.

Don’t use Memorex DVD media, TY and Verbatim is choice #1.

Thank you very much chef.
I just called NEC tech support and the guy told me not to use Memorex DVD+Rs as they are not compatible with NEC 3540a.
I think I am going to get some Ritek(TY brand right?) and test the drive once again.
I will keep all of noobies like me updated how I do.
Thanks again~

You might want to check www.videohelp.com/dvdmedia for dvd media results.