The NEC 2500a seems to be a popular DVD writer these days. It burns DVD+/-R at 8x and DVD+/-RW at 4x. It's biggest claim to fame is its media compatibility, especially for DVD media. With most DVD burners these days, you have to be careful with what brand of media you buy, but the NEC can handle almost anything you throw at it. Check out doom9.org's DVD Burning forum, or the CDFreaks review
, to see all the positive comments. I just got mine on Wednesday for US$88, and the drive is offered with beige, black, or silver bezels.
The noise when it's burning isn't bad at all. It's just a "whoosh" sound, and not a very loud one at that. It doesn't make my case vibrate nearly as much as my Aopen CD burner. However, if you leave a DVD in the drive, the drive emits a faint whine, even after spindown. It's probably no louder than a typical Maxtor or Western Digital drive's whine, but still, you can't leave discs in this drive if you want a silent PC.
As for DVD readers, all I can give you is a thumbs-down on the Pioneer DVD-120. I bought a DVD-116, which was pretty good if I remember correctly, and then it broke within the warranty period, so I was sent a DVD-120 as a replacement. The whoosh made by this drive during playback makes watching DVD's no fun. The NEC drive makes about as much whoosh sound when playing movies (I haven't made any direct comparisons), but it doesn't have any of the Pioneer's rumble. I also had an Afreey 12x DVD reader a couple years back, but that broke after a year. It was a good drive for watching movies and ripping DVD's, but I can't remember if it was noisy. Check out Lite-On's offerings, because from what I hear they only spin at 1x if a DVD movie is in the drive, whereas some drives spin at 2x or even maximum speed. You can also then use K-probe, a useful CD and DVD burn-quality analyzer that only runs on Lite-On drives.