So I create this great Nord warrior, with nice long blade skills, agility, and 30 hp per level. The problem is.....he is getting killed by a thief. In the beginning dungeon, I read that it was supposed to be easy, but alas, I cannot kill any of the humans. I mean, a Nord should be able to take down a thief, no? Am I doing something wrong?

One walkthrough said, "The Thief isn't too terribly tough, but he is a fast attacker", my ass he isn't tough, brings down my nice nord in 3 hits.
Mind you, I have quite a bit of knowledge with tes, having played Morrowind and Oblivion, but this is driving me insane!!

The beginner dungeon is actually quite tough in Daggerfall. You need to watch out also for the imp right next to the exit, as he can easily 1-shot beginner characters depending on magic resistances and such. Save a lot in the beginner dungeon, and bypass monsters if you aren't strong enough to handle them. Frankly some class builds just can't handle a lot of fighting in the beginner dungeon and the best thing to do is just try to hurry out.

In actual combat, try swinging and then quickly backing off. NPC's stand still while swinging so if you do it fast enough you can dodge taking any hits.

Are you sure you are using a long blade? You do not always necessarily start with one, regardless of your skills.

With 30hp/level, your difficulty dagger is pretty high - you might try lowering that....

JimC

The thief is cake. Wait until you get to the skeleton on the way out! He's fun to whip on. Thief is cake, you just have to learn the combat techniques in Daggerfall. I tend to go down the stairs to the thief and slash followed by immediately backing up. The thief generally can't follow you up the stairs, so you run in and swing, then retreat. The skeleton is best defeated by walking backwards while swinging like a mad-man, although you could go the panzy way and avoid him, but it's a longer trip.

Ramp up your speed stat. I effects your swing speed and with a speed of 100 (which is possible to reach by level 2), you can shred most enemies easily.

Not necessarily. If you've got some acrobatics, you can lure the skeleton away from the throne, run around him, jump up on it, flip the switch, and rise to safety.

No, I set a few disadvantages so it is very low actually.
Magic disadvantages.