if others are sending emails from your hotmail account just change your password
https://account.live....section%3D1&mkt=en-gb
if you really want to shut the account change your password first then
https://account.live....section%3D1&mkt=en-gb
I say change your password first because if you deactivate the account without changing the password then the spammers will be able to reactivate it just by trying to use it again with the correct password (which they obviously have)
incidently this problem is almost always caused by the user entering their details (includding password) on some random website or other that claims to do something like show you who has blocked you on MSN.