I'm on a XC 29r Full Suspension... 100mm front and back.
Handles pavement, dirt roads, gravel roads, fire roads, mild single track with the small knobby tires I put on.
Kenda Small Block 8 and now Vittoria Mezcal tires.
I'm not into Downhill or rock bound single track...(although I like going downhill)
With your size I'd look for large/xlarge frame/19 in. 29r. w/good airfork in front at least.
29r rolls over stuff and rides better on pavement.
I never put the bike in car... just ride to trailheads.
Good on you for starting with old bike to know what your riding style/needs are.
Oh... and I'm a senior citizen.