Welcome to Android Forums! It's a really great community, imo, one of the nicer ones. And congrats on the phone, it's a huge jump from dumbphone to this, but sooo worth it.
Alrighty, on to Hotmail. To set up a new email account, go to the Email app first. I'm nearly positive it's default on one of the home screens, but if not you can go to Applications and scroll through the pages to find it.
Inside the app, tap Menu (the softkey button at the bottom of the phone) then Accounts. Next go to Menu > Add account, and enter in your hotmail information. Since you said you wanted it to be default, make sure you check the top checkbox as well. No big deal if you forget though, this can always be changed later. You can either hit the Enter key on the keyboard, or the Back softkey button to get rid of the keyboard, and then tap Manual setup, followed by POP3 account.
The username/password should already be filled in for you - though be sure to add the "@__.com" part, it likes to leave that part out. For the rest of the boxes, use the following:
POP3 Server: pop3.live.com
Port: 995
Security Type: SSL
Delete Mail from Server: Never
And hit Next again. For the Outgoing settings:
SMTP Server: smtp.live.com
Port: 587
Security Type: TLS
Leave the login part alone.
Login information source [here].
Now just select how often you want it to check (and mark your preferences on the other two options) and hit Next again. All that's left is to give the account a name (I'd be boring and go with Hotmail) and finally hit Done and let it load.