Your email address can only be spammed for one of three reasons:
1. You've used that address to buy something, or to sign up for something (such as AB membership) on an insecure website, which has been hacked to gain lists of valid email addresses. (Solution: Always use a
different email address for each website).
2. You've placed your email address on your own website and it's been harvested from there by web-crawling software. (Solution: Put your address onto a jpeg image and place that on your website, rather than using text).
3. You've used an address that can be easily guessed at, such as
[email protected] or harrybloggs@gmail. (Solution: Use a non-guessable address, such as 617h45bloggs21@gmail).
Also use a decent email service in the first place!
http://www.gmx.co.uk/
Instructions for closing an Outlook.com account are here: