You're off topic for this forum, which is dedicated to Windows Live OneCare.
However, what you are facing is pretty common these days, unfortunately. Someone thinks that your Hotmail account belongs to them. They have used your email address to sign up for newsletters. They probably also used your email address on various web sites, hence the increase in spam. There isn't too much that you can do. I have two accounts that get the same activity and clearly there are two different people think that the addresses belong to them.
You can safely ignore the password resets and make sure that your actual password is strong. Make sure that you also have the secret questions for your account. Set up the spam filtering at as high a level that you wish.
If you don't want to deal with all of that, abandon the account and sign up for a new one. http://account.live.com
If you want to contact support - http://support.live.com
-steve
