iirc there are two 'grades' of class 3 lasers, those which are too strong to be class 2, but still under 500nw (which is 'safe' as long as you don't stare into it for more than a few seconds), and those which are above 500nw (which is unsafe but won't set things on fire) but not strong enough to be class 4 (the nasty shizzle).
DVD players fall into the very bottom of the second third class, generally being between 500 and 1000nw in power, but it's a pretty big class for memory. Blu-ray players seem to be about 400nm, according to wiki.