It has to be said, DDR remains great and timeless fun, imho. I came across someone who still plays that, he had it on PC with a shitload of songs. I still have a imported 10th Edition disc for PS2, which has some 110 songs or so and back then was considered the best. I really enjoyed having a go again, and it remains great exercise too.
Singstar PS3 I think plays all the PS2 discs, but I'm not sure. Singstar PS4 does something similar with most PS3 discs, no idea if PS2 discs would work though. I have a Dutch kids Singstar disc however that does not work with the PS4 version. Haven't tried the other discs yet. Perhaps I'll try that out tonight or this week.
PS3 version Singstar (and not the latest version that just came out) seems to be the best Singstar currently out there, with even Move Dance Songs that were quite decent. I also thought the Move Dance Star game was one of the best dancing games for PS3 with very accurate Move tracking. And the somewhat tacky Sports Champions is still one of the best motion games out there, imho. Just amazingly natural motion controls, just like the real thing. And Move Fitness is also one of the best fitness things out there, especially if you like boxing exercises.
As for media, consoles are not likely to ever compete with boxes that are free of big corporate digital rights management pushing stuff, but the Xbox One surprised me with among others MKV support in a recent update. But otherwise, those roku, popcorn etc boxes are hard to beat. You have versions that have a Netflix style interface to illegal downloads for everything, and they are hard to beat if you just don't care (I am not one of those, always pay for my stuff, but let's just say that in the Netherlands I am in the minority for sure).
On the PS2 I also really loved the Time Crisis and Point Blank games. I think Point Blank was actually PS1? But it was one of the best party games out there, everyone loved it.