Ok, I have gone and reviewed the page for the plugin, installed it sucessfully on DreamHost, and looked at the code.
I have good news and I have bad news . The good news is that I have sorted out the cron settings; the bad news is that this plugin (which was last updated over a year ago) requires PHP URL file-access to be enabled in the server configuration. Without this setting, the plugin will not run, and returns a fatal error.
Having this setting "on" is a significant security risk and, as such, is not enabled by default on DreamHost's default PHP installations. While you could compile your own version of PHP for use on your domains and enable this function in order to run this script (search the DH Wiki for further info on compiling your own PHP), doing so would decrease the security of your site(s) (and possibly your shared server!), and is not supported* by Dreamhost. I'm sorry, but I also will not assist you with enabling that function and introducing that risk to the server. If you attempt it, and succeed, it would be "your baby" and your responsibility.
You do have other options:
1) You could modify the code in the plug-in to use cURL, which would allow the pages to be grabbed in a "safe" way. Here is a link that purports to have the necessary modification to make it work on DreamHost using cURL Yeah!
2) You could use any number of other RSS aggregators that are available, some as WordPress plugins and others as general packages that you can easily integrate within a WordPress blog, that do not rely on this function and that do work on Dreamhost. One such WordPress plugin is FeedWordPress, which has been successfully installed on DreamHost.
Hopefully, one of these solutions will get you "back in business"!
(edited to provide a cURL solution to the OP)