That sounds an excellent plan. I envy you your nice long holiday to do family research in!

You might find the following website useful. It gives details, with online links, of all the County Records Offices in England, Scotland and Wales, which you can visit to view local parish registers and other records.

http://www.familybmd.com/recordoffices.htm

I would ring or email before setting out to confirm opening times and to check that you don't need to book a table/microfilm reader - some Offices are very busy!

Research-wise, I think it's a good idea to start from the last (i.e. most recent) person you have concrete evidence for and work back step by step from there, alternating births and parents' marriages (with a weather-eye on deaths) and comparing with census records, etc, so that you can be more confident that you're keeping to the same family line.