I will suggest Mac even though I've been using Win Laptop for the past 5 years. Simply because managing photos via Apple Photo is way easier if you're thinking using 3rd party photo management software.

In term of learning curve, believe me, learning to use Mac is so easy. Running Lr & Ps in there also smooth. But if you still insist on using Win laptop, just get any with huge storage and better display. I don't think you need that much graphics capability just for photo storage and minor Lr & Ps.