Row 18 or 19?/OLCI or CI?

Morning 
Just a couple of quick opinion based questions if you would be so kind to answer pls:
1) Booked on VS045 in PE an currently in 19D&F (i think) was originally wanting to move to row 18 in one the 2's coz i thought it was an exit row, i now understand its a bulkhead so, which would be better as I've heard/read that the bulkheads aint to good (cant stretch out feet etc)?
2) If I've got my seats reserved, ie row 19, should i need to worry about doing OLCI or should I be ok to just check in at the PE desk when i get to Heathrow and get my reserved seats? but... if i wanted to get row 18 how early would i need to be at the airport to get it, unless i can get them with OLCI??
This is my 1st time PE and Im just slightly confused, but excited too!!:D
Thanks in advance
Neil

Just a couple of quick opinion based questions if you would be so kind to answer pls:
1) Booked on VS045 in PE an currently in 19D&F (i think) was originally wanting to move to row 18 in one the 2's coz i thought it was an exit row, i now understand its a bulkhead so, which would be better as I've heard/read that the bulkheads aint to good (cant stretch out feet etc)?
2) If I've got my seats reserved, ie row 19, should i need to worry about doing OLCI or should I be ok to just check in at the PE desk when i get to Heathrow and get my reserved seats? but... if i wanted to get row 18 how early would i need to be at the airport to get it, unless i can get them with OLCI??
This is my 1st time PE and Im just slightly confused, but excited too!!:D
Thanks in advance
Neil