Think Creole is to french like scottish to english
sometimes I can catch up something but speaking myself is a bit time consuming since I search always the words. you find a lot of french sound in this. seem to be more written like french is spoken. but some english words are also found in it. ex. bon weekend ( hope that was right)
I really liked it in Ireland, had quite some luck there with the weather, and once got me a sunburn on the aran's (windy, sunny, terrible mix for a blondie) after a rainy day in got to clifden and asked for something against sunburn in a pharmacy. They guy looked pretty puzzled: Here...in Ireland?
But they can have some heavy rain here too, maybe not so much over several days.
I really like the black magic as well as Cider. I even worked a while in an irish Pub at home in Germany to get this stuff for free
There we got the same stuff like in Ireland.
Beside this I always prefer a good irish whisky to a scotch. (except Scapa, nice stuff, but an irish guy told me, that because its made of irish barley)
To your last question, don't know really how it is with the normal people here but in a shop you should normally find somebody speaking english, since it is the official business language here.