Hi,
Ok, I investigated this problem and here is what I found.
The Show Feed Name setting enables showing the feed name and link above or below the feed items. The url used does not come from the url entered as the web site url for the feed, it comes from the actual rss feed in the <channel><link>
The bug was actually in the blog RSS.aspx and has probably been there for a while. It was populating <channel><link> with SiteUtils.GetCurrentPageUrl() which used to work there but a few versions back we changed the feed to combine url paremeters and the pageid parameter is no longer a separate parameter in the url so the SiteUtils.GetCurrentPageUrl() was returning the home page url instead of the blog page url because with no pageid the default page is returned.
This is now fixed in the source code repository and on the demo site.
Thanks for the compliments on mojoPortal!
Best,
Joe