If you are being prompted by Hotmail to complete a CAPTCHA box before sending an email it's an indication that your account is sending too much email and may have been compromised.
Immediately change your password and the follow the rest of these suggestions :
http://www.emailquestions.com/email-discussions/2714-someone-hacked-my-email-account.html
Immediately change your password and the follow the rest of these suggestions :
http://www.emailquestions.com/email-discussions/2714-someone-hacked-my-email-account.html