Having problems with Mercury /32 . Please HEEELLP MEEEEE !!!

[driverm]

Hi. I bought an oscommerce web site and i am trying to learn the specifications and other site/related things in my computer. So i downloaded and installed xampp. During registering, web site tries to send email for authentication. However, I find out that it cannot. (at that time, i did not started Mercury) Then I realized that i need to start Mercury. In order to test it, i tried to send a test mail but it gives me the error:

Temporary error 249 (temporary MX resolution error) resolving 'yahoo.com'

I have checked internet but I could not solve it. I looked for my DNS from ipconfig /all. There are two DNS servers.

Please help me on this issue. I need to start working with my web site as soon as possible...

Thank you for all your potential time and help on this subject in advance

PS:
- I am using XP.
- In web site configurations, there is a line that is named " E-mail transport method".

There, it writes that "Defines if this server uses a local connection to sendmail or uses an SMTP connection via TCP/IP. Servers running on Windows and MacOS should change this setting to SMTP."

So i choosed SMTP as my email transport method. Is that right?