Gmail – Turn off GMail mail delegation notice

If you already have the addresses in a group, two methods come to mind.

1. Open the contact manager and select the group you want to send to. Click the "select all" checkbox to select all members of the group, then click the email icon that then appears.
2. Start to compose a message. In the to field, start typing the name of the group. Before you get too many characters in, you should see the group listed in the drop-down menu. Select it and the email addresses for the whole group will be put in the to: field.

If you'd just rather type one email address and have it go to everyone, there are a multitude of services where you can do that. Google Groups is one. (But that's probably overkill for five people.)

You can enable the Inserting Images Lab.

I don't have an email client set up to test receiving inline images, but sending an inline image from another account with it enabled works fine.

Source: http://gmailblog.blogspot.com/2009/04/new-in-labs-inserting-images.html