That's one way to do it - but you can attach up to five photos is you do it from the photo thumbnail view of the Photos app:
<img src="http://www.ipadforums.net/attachment.php?attachmentid=28149"/>
In this picture, you can see all the photos I have. I first tapped the curvy arrow on the upper right and then selected one photo (the picture is the result of that actin). The "Share" button on the upper left is then highlighted. If I were to press it, one of the options would be to e-mail. Again, you can select up to five photos this way.
Hope this clarifies.
Marilyn