Hi cj78,
You can recall the values from your fields in your email message by using #field_name# in your email text body.
The alternative is to have many different email send fields, and use the SEBLOD fields Restriction plugin to enable / disable them based on the values of other fields:
http://www.seblod.com/products/19160
I haven't tried this solution before, but I believe from my understanding of this restriction that it will work. Proceed with caution though, if it does not work I don't think you will get a refund on the purchase... Just a warning.
Cheers,
J