How do I change my default email to yahoo instead of this Windows mail?

I have a Yhaoo mail account that I use daily. I have an account with my internet provider that I do not use (just had 900+ inbox). I was on a ';for sale'; list and wanted to respond to a post. Of course the Windows account is default. How do I change this? Thanks in advance for all the help.How do I change my default email to yahoo instead of this Windows mail?
If you're using Internet Explorer.



Click this link, from Yahoo, for detailed instructions on making Yahoo your default mail client on Internet Explorer.

You WILL be required to download their ';newest'; toolbar----use the ';download'; link that is on that page, to be sure and get the correct one.



That download adds Yahoo! Mail to your PC's list of email programs so you can choose it.



Then, after you've chosen Yahoo! Mail as your PC's default email application, Yahoo! Mail will open when you click ';any'; email link in ';any'; browser.

http://help.yahoo.com/l/us/yahoo/mail/or鈥?/a>