Roger, I have been trying to find the same information... there are a couple pay for info sites for Ireland, but I can not find which is best.
I have the world subscription here, it has helped me tremendously with my Welsh ancestors, but not my Irish ones [I'm sure there is little hope for them].
I have no idea about the 'rest of the world' as my entire lineage came from the UK. I would take a look at the listing of resources available here for your country of choice and compare that to other sites. There is a listing on here of all records that you can view for free.