Hi Paul - This is because the DNN Country field within DotNetNuke/Dynamic Registration saves the country as the text and not the value (why I don't know but thats how it works
). So, you need to change your search to be Text as SearchOption and Text as SearchOptionValue instead of Value as SearchOptionValue.
You should also look to upgrading to 4.0 as there are many new enhancements!
Thanks,
Chad