So, I have to admit, I'm an idiot. I just got the Morrowind for the PC, with the construction set, but I don't even know the basic controls to move around the texture window yet. Is there anyone who would be willing to kind of take me under their wing and explain in painfully specific detail what i need to do?

Instructions we can give you will vary depending on what kind of mod you're trying to make. How to do it all depends on what you want to do. Unless you'd like to learn to fully use the construction set for anything you may want to do, then we might want to find you some tutorials.

I've been playing with a bit of stuff but i still need a lot of help with the NPCs, how to give them topics to talk about and such

I have just the thing for you then, let me go find it real quick...
EDIT:
Here you go.
http://www.gamefaqs.com/pc/913818-the-elder-scrolls-iii-morrowind/faqs/17064

Thanks

You can also check the Tamriel Rebuilt site, they have a good collection of tutorials.