Embark skills matter less than you might think, because dwarfs can pick up skills on the fly pretty quickly and even an untrained peasant is serviceable at most tasks. Generally I go with two max skill miners, two max skill growers, two soldiers (all points divided between Armor User, Shield User, Dodger, and a weapon skill), and one expedition leader/doctor (one point each in Appraiser, Judge of Intent, Organizer, Bookkeeper, and Diagnostician). That covers shelter, food, defense, and trade. From there you can divvy up the more important crafting skills (Carpenter, Mason, Stonecrafter, Armorsmith, Weaponsmith, Mechanic) among the non-soldiers as you see fit. You'll want to assign stuff like woodcutting and brewing after you embark, but it's not worth investing in now.
For items, the essentials are 2 picks, an axe, an anvil, some Plump Helmet Spawn (they're cheap, so bring 20), and enough food and drink (40 and 60 respectively) to survive until the first autumn caravan shows up. Generally you'll want some dogs and cats for various useful purposes that may or may not involve eating kittens. If you want to try your hand at livestock, get some turkey hens (cheap, easy to manage, and lay a ton of eggs).
The default item package has a bunch of pre-crafted stuff that's useful to have around, but most of it is easy enough to craft on site that you're better off buying raw materials like leather and thread.