Are you possibly looking for Content Editor Web Part that opens list items in a new window? Could that be what the MSD2D article is referring to? I am not sure if this will work for what you are doing (pretty sure it won’t) but you can try.

mindsharpblogs.com/.../654.aspx

I had a look at the web  part
you suggested (what that man can do with a CEWP is incredible!) and in
think in my case I can't use that solution as the links  I am trying to
open in a new window  are within a page  Viewer WP on my home SPS page
along with other web parts, whereas in Todd's webpart you need to have
just the list or document library open  to add his CEWP below it. If I
am wrong about that by all means let me know. Seems like a pretty
simple thing I want to do but no joy so far.

Yeah I agree, I don’t think it will work. What is the URL to the MSD2D article?

It's not an article, just a post  on a discussion board. The link  is
www.msd2d.com/.../default.asp

Alright, in this particular post, they added  a ‘target=”_blank”’ to the A HREF tag in the code for the banner image. I don’t think this will be an option for you, because that would mean in your actual site, every link  would launch a new browser window. Your hands are tied when you use that Web page  Viewer part  since all it does is pull in the rendered page and you don’t have control at the site level over the referenced content.

Put a <div> tag before the page  viewer Iframe tag and give an id to it. Now in your JavaScript loop through all the anchor tags and add target="_blank" to them.