As a decently tall rider, you'll likely appreciate the geometry of a 29er over 27.5. A hardtail 29er is a good starting bike. For steep rocky/rooty areas, or bumpy high-speed descents FS is nice, for flatter areas, hardtails do quite well.

The best way to decide what type of bike is to look at what the other riders on the trails you want to do are riding. If most are on hardtails, you'll be fine with a hardtail. If 90% have FS bikes, then you may want to consider a FS bike.