In my email views, I usually just do something like...
- Name
- Value
Should
Depends entirely on the email client that receives it. In my experience, most email clients that will interpret HTML don't care if you have full body/head/html tags, etc. In fact you don't even need those tags for most browsers. You need to have the head tags to include style/title, etc. Otherwise they are not really necessary, per se. I've never seen them to be necessary.