Guild Wars 2

Hey, Guys. Just almost finished all the mastery points in Verdant Brink. Only 2 left.
I just want to know which mastery skills are required, so I can save the mastery points?
Right now my gliding skill is at level 3.
and I am heading to Auric Basin.

Thank you.

Something is really confused me. I know a lot of things could do after level 80: Dungeons, Fractals, PVP, HoT map completions. However, those things are complicated to me right now.
My initial though is to finish the story in Maguuma. However, I am stuck into one task since I cannot find the NPC, and I am always been killed on my way to the story quest which makes me really frustrated.
Then I turned to practice dungeons. But I am not that confident on my gear since I do not spend so much time thinking which gear is better for me.
Back and forth, I feel really discouraged.
Any ideas, suggestions?
Thanks.

Dont know why after I hit 80, the maps become really offload.
Any suggesstions about the laptop to run the GW2 fluently?
My budget is around 500-600 USD.