Integrating social networks into wordpress native comments

I’ve been looking for the ‘perfect’ comment system for a wordpress blog I’m working on.

First, there is Disqus/intensedebate/etc… :

Pros: Easy to set up, somewhat customize-able (to a limit), removes load from your server, social.
Cons: Syncing with wordpress can sometimes be a problem, external bugs can ruin your comment flow, there’s no fallback for javascript-less users, lots of embedded code.

Then, WordPress native comments:

Pros: Deeply integrated with the blog, highly customize-able, saves the huge junk of javascript thats being embedded into your blog, easier to provide fallback options
Cons: Not native-ly social, ???

For me, WordPress comments would seem like the best option.
The only problem is the social integration.

My questions is ;
what do I do with the data I receive by the users AFTER they log into a social network? (I already know how to create the login gate and get the required info back…)
I thought about simply saving their; email, name, picture (which you get from the social network) like what’s being done when people comment without a social network…
The problem is I don’t have any experience with the wordpress database and I have no idea where to start. Normally my best bet would be to use the wordpress codex but I couldn’t find much there.

P.S; Please, no plugins!
There are amazing plugins out there but I love to learn to do stuff by myself.
If someone could just throw some useful links to me or theoretically what needs to be done, I’d be super thankful!