Skill Unlocked Packs purchased from the online store.

If say, I buy the skill unlock packs, all my characters in PvE would have all skills normal and elite unlocked for them without me having to get them from the skills npc or capture them anymore in the game? If that is the case, do I also get the elite skill hunter title as well?

No. Skill Hunter isn't about having the elites unlocked, it's about having them on a certain character. The unlock pack doesn't make a difference, unless you wanted to get them all from elite tomes.

No, you will not automatically have every skill on your own characters. But.... the Skill unlock packs unlock every skill in the game for every hero on your account. So they will automatically be able to use any skillbar you throw at them.

you will have all of them for heroes and PvP only charactersuse tomes you can get them for Role Playing Characters. if you

Without the skill packs a skill would only be accessible from certain skill trainers. Once you had aquired that skill on one character it would then be unlocked, making it available to be bought by all your other characters at all skill trainers in the chapter that skill is from.
Unlocked skills also are available for any of your heroes and for any PVP-only characters

PVE characters still need to buy (or use a regular tome) normal skills, and to cap (or use an elite tome) elite skills to be able to use them.