Go for full suspension if you are doing anything remotely downhill/trails, hardtail for cross country. I travel to Hamsterley Forest from Newcastle in less than an hour and it's brilliant. Red and black graded trails are enough for me but they've also got a novice friendly skills loop and Danny Harts downhill for the mental/brave.
Cheers Jay. I'm still keeping my out out for one. Missed out on a few on the bay, still no idea if the ones I'm looking at are decent or not but got a rough idea of what the general value is of some models.
Look for something around 120-150 suspension travel, you can lock out the suspension front and back in one second when climbing. Also a dropper post is essential because you need to hang your arse low and back when going dowhill. A dropper basically lowers the seat by a push of a button and you can raise it again when climbing.