I am thinking of doing a kind of death knight build, Except that he would be a basically redeemed version (using his dark magic to take down corrupt and evil enemies like the Silver hand and such). I need to know some of the skills that would be best, and maybe be able to figure out some of the quests.

Have some of the info right now:

Race: Nord (makes the most sense)

Stone: Either Ritual or Atronach. Maybe Lord

Skills: Likely two handed, Definitely Conjuration, and heavy armor. Unsure of the rest.

Any advice is welcome.

well illusion seems perfect for it, although i dont know if Silver Hand is considered evil enemies, i mean of course we know they are evil, but only because Bethesda made them act like that in the game cuz their ideas are actually pretty good i mean they want to kill werewolves, most of the tamriel citizens dont like them, so if im going to Roleplay then i wont consider Silver Hand a bad faction unless i am a werewolf!

maybe he will want to join the college to use his magic better and do bounties every now and then.

and Alchemy seems reasonable enough to!

Smithing to improve your armor and weapons.

Restoration to heal yourself and your reanimated creatures and thralls.

Either Illusion for rally,courage and call to arms to use on your thralls(once you get the master of mind perk)

Or enchanting to reduce magick cost of your conjuration and restoration spells.

and what about fighting dragons? I might do the main quest after a while.

And what about weapons and heavy armor? What should I use?

My Death Knight used Conjuration (to raise the dead and use Bound Battle Axe), Destruction (Frost Magic at ranged instead of Archery) and Heavy Armor. It was a lot of fun, my brutal orc.

SO, what would be the back story/reason behind the character using dark magics such as necromancy?