Both of the bikes you are looking at would be a great option. Remember; a more aggressive tire and bike can be road on pavement easier than a skinny slick on gravel/dirt. I am normally one to give up a top gear in favor of a lower gear knowing that at some time I am going to need it. Also later on, if you are maxing out in top gear and feel like you are spinning you could have a local bike shop help to re-gear the bike so you have a bigger top end; or buy a second bike!
Tires? either would be fine. 29's roll easier of bumps but are heavier.
Your height and size gives you lots of options. Get whatever bike you feel more confident with and then later you can get a second bike(or third) secondhand from someone who is looking to upgrade to a lighter road bike or a better MTB. I am 6ft and 175lbs. All three of my bikes I bought second hand for 1/2 price when the original owner wanted something newer/faster/better. Great way to get a $1,000-$3000 bike at a great deal.