I am using Gmail. So far so good. To prevent email spam, there are some tips to follow, you can check this http://www.wordsandpeople.com/security/how-to-prevent-spam.htm .

You can try gmail or yahoo/y-mail (which is practically spam-free). You may like to create some filters or even an exclusive "white-list" to wipe out these irritating spam mails. As for irritating ads, go for an ad-blocker add-on (just customise your options in IE/FireFox). Good luck :-)