Windows 7: emailing a pic

How do I set my default email program to 'yahoo'?
When I go to email a pic from my pictures library, it says it can't because I don't have a default email client set up.

You set up default, by typing default in search. Then going to the appropriate setting in default programs. .

But I do not know if you can do this with Yahoo

You could set up the email client. To use Yahoo on the client you may need the pay service.
Yahoo is web mail; however, I have heard that you may be able to use it with Yahoo Messenger.

If you want to set up a client go to Windows Essentials and download Windows Live Mail.

http://download.live.com/

If I do set up Windows Live Mail as my client, when I email someone something, and they want to respond, whose email address would they use.
I suppose you can tell by my question, I'm pretty confused.
I guess what I'm saying, is I don't want to set up another email address.
I never liked outlook express.

If you are trying to use Yahoo webmail, maybe the following link
may help.... (I can't vouch for it)
PC Hell: How to Set Yahoo As Your Default Email Program

PC Hell: How to Set Yahoo As Your Default Email Program

Went here & d/l program, but still nothing.