>>MAPI is a standard way to send email through default email client as long as the client supports MAPI.
>
>I guess I'll ask my client on what he prefers. Do you think most commonly used clients would support MAPI?
>
>And, can you point me to some code samples?

Yes, most popular email clients support MAPI. I provided a link to UT MAPI download in this thread. You can also find MAPI samples on Craig Boyd blog at http://www.sweetpotatosoftware.com/SPSBlog/.