Monkey Island SE is great, it's one of the few adventure games I would recommend to people that aren't already fans of the genre. Some of the puzzles are obtuse but the new graphics and music do a perfect job of making the PC classic enjoyable on your console & tv.
FC Blood Dragon looks excellent, apparently I bought it at some point and don't remember but it showed up in my "Ready to Install" list as soon as it became backwards-compatible. You can check out my thoughts here: https://www.youtube.com/watch?v=dQw4w9WgXcQ
Super Dungeon Bros seems like an entertaining Diablo-lite and a good alternative for folks that don't want to grind in Happy Dungeons.
Our own Kat did an excellent review* for Murdered Soul Suspect and you can read it here to decide if it's worth the download: http://xboxamerica.com/articles/this-is-not-a-love-letter-kats-review-of-murdered-so-1
*review pertains to the 360 version; the GwG download is the XB1 version and may be, as she said, prettier and buggier.