it sounds like your email seetings are making your emails appear as text only.
I know that some web sites allow you to view their pages as text only, which is a feature you can switch off and on, but dont know how to change defaults for email views, that would probably depend on which email system you use. you may have to ask your email provider.. which of course you may already have tried but to no avail.
if its a web based email provider you use, hotmail and yahoo both allow links/pictures in email, so you could consider swapping to them.