may have gotten bug in an email

Hi All.
My problem basically is that I am an older, non- computer literate person who doesn't know how effective various viruses and malware are, or their mode of operation. From reading Daniel Suarez's books I get the idea they can do anything. I have opened an email in my longtime primary email service that had a kind of logo image. My service opened it in plain text, but I switched it to html and activated 'load image'. The image wasn't dirty or anything; very innocuous. I ran free 'avast' and then free 'hitman pro' and they came up clean.
This email service doesn't download in conjunction with outlook or outlook express. You have to set up the paths I guess you'd call them and then download. I worry if I download the messages i want to save that I will also download any malware. Usually if I discontinue an email service, I send the messages I wish to save to another of my email services, but there again I worry I could be infecting those, so on. I do want to stop this email service. I spoke to the provider about changing my email address, but they don't let you.
So I am posting this to ask you all who are far more knowledgeable than I about these things, how best to proceed to keep myself as private and safe as possible.
Alterintel

 

However you run your email, e.g. in a web browser as you do, or in an email client such as MS Office Outlook or Thunderbird, there are a few basic rules for avoiding unwanted content -

- Don't click on any hyperlinks to websites unless you know the person who sent it, exactly where it will take you and you want to go there

- Don't open any attachments unless you know who it's from and have asked for it to be sent or are otherwise sure it's safe

- Don't click on options to view pictures (html content) unless you are confident the site emailing you is a safe site.

That's about it really.

 

earthling, thank you for reminding me of the tips, which I learned of in past. I am hoping someone can answer my question.
alterintell

 

I thought I had. Perhaps you had better have another go and try making it a bit clearer.