Apart from windows live mail (msn mail) windows 7 does not offer a "outofthebox" mail solution.
So there are two options:
1. Obtain Microsoft Office (outlook is in this package)
2. 3rd party software
A good example for 3rd party mailing and also a good program is available from Mozilla called Thunderbird.
See this link:
http://www.mozillamessaging.com/en-US/