Web-based Email Clients that Are Safe
Many people use the most popular free mail services such as Hotmail, Yahoo, and so on. Those services currently don't offer the capability to turn off HTML emails. For those people who want to make their email accessible via the Web, there are several freely available clients that work with the Internet standards POP3 or IMAP. This means you can easily replace the troublesome Outlook Web Access with something safer and easily modifiable.
IMP (http://horde.org/imp/), the Internet Mail Program, is another Web-based, fully featured email client that doesn't by default display HTML emails. IMP is part of the Horde Project, which is a platform for Web-based applications for productivity, messaging, and project management.
Microsoft shows the way: http://support.microsoft.com/directory/article.asp?ID=KB;EN-US;q165531.
If you only have Outlook Express installed on your computer, you are better off NOT using it and finding another email client such as Eudora (or even a different operating system whose focus is more on keeping your data safe rather than turning on features that make you a target).