If you are going to be doing anything in the UK there is a book called lasors.
http://www.caa.co.uk/docs/33/srg_lts...Bookmarked.pdf
Right click on that link and save cause its huge.
It details all the pre course requirements for the various ratings and licenses. Section E is IR.
Xcountry in the UK is anything which is more than a couple of miles away from an airfield or something like that. Alot of folk in the UK do circuits which could be counted as xcountrys.
PIC is when you have signed the techlog as the captain of the aircraft. ie there isn't an instructor on board or an examinor just you and whoever you have taken for a flight.
Some of the stuff can be a bit confusing so once you have a read of that document come back with any questions.