Yes, BCN has one large terminal for all international flights and it is pretty easy to navigate. As for LeMeridien, I was there last month and had no problem getting an early arrival/checkin at 9am! Call the hotel before your arrival and request it, telling them that you'd appreciate it, and realize it is subject to availability yada yada.... Not sure about an arrivals lounge at BCN, and CO shares a common business class lounge that is beyond security on airside, so don't know if it will be possible to go back there and wait---Call CO and ask about either an arrivals lounge or if they have an arrangement with a local airport hotel. LeMeridien is only a short 20min cab ride away, but if you can wait for your friend at the airport, so much the better.