Some helpful tips and some general info:
Go to a bike shop and get fitted! Since you're a newbie, you need their guidance to get you on the right sized bike. Your decision to stick with a hardtail is wise, you'll get a better component package and a good bike.
Helmets: Bell and Giro are both owned by the same Co. and made in the same factory. Bell's tend to fit a rounder head, Giro's a longer (oval) head. There are a lot of other co.'s as well, Briko, Louis Garneau, Pryme,....etc.
Pedals: I'd stick with regular platform pedals for at least a year. Learn how to ride your bike and bunny-hop/jump with platforms, then next year upgrade to clipless. You'll be a better rider learning to manuever (sp?) your bike w/platforms, and it'll pay off once you switch to clipless.
Other things to consider: I'd highly recommend some padded cycling shorts, you can get either lycra or baggies. Also, get some gloves. I recommend full fingered, for more protection. I also use a jersey made of a performance wicking material. I like using a Camelback for carrying my water, spare tubes and tools. I find it better than water bottles and a seat bag.
Things to carry on your bike (Tools): A spare tube, a patch kit, a mini-pump, a mini-tool (folding tool with 4,5, & 6 mm allen tools, flat blade, and phillips blade as a minimum), a first aid kit,(gauze bandages, antiseptic, latex glove & tape), a chain tool, and a spoke wrench. I also carry some change, and a couple of dollars. What else, I carry some zip ties, and a spare crank bolt. Obviously I carry a lot of stuff, but I throw it all in my Camelback and hardly notice after a few minutes.
With everything mentioned, you should be able to handle any trailside repair, and if not, you'll have change to call home for a ride! BTW, if you rip your sidewall on your tire (not tube) a dollar bill is a great temporary patch fit inside where the blowout occurs. I also wrap some duct tape around my seatpost numerous time. Duct tape is a wonderful thing! I have a black post and I found some black duct tape and you can hardly notice it!
As far as glasses go, I recommend one of those straps that keeps your glasses on your head. Here in the US, there is a brand made of a neoprene material called Croakies that works great!
Good Luck & L8R
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"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming, "WOW, What a Ride!" - unknown
"Your Bike Sucks" - Sky Yaeger