Hi nancy and welcome to Poe. (Pictures of England) you are talking my country here (although I'm a Lancastrian lol) its usualy less expensive to fly into Manchester from the States. if you are hiring a car its 'motorway' (freeway) from the airport, around Manchester and on over the Penines (hill chain) towards Yorkshire.
If you log on to the AA (Automobile Association) or RAC (Royal Automobile Club) Web sites in the UK you will get loads of info. also mileage and time calculator.
If, as you suguest you base yourself around the Thirsk/Harrogate area are you will find something of interest each and every day, a maximum of 2 hours drive in any direction. Must see's are-
York, a walled city with a fine 'minster' and supurb museums.
Howarth, Olde worlde village, home of the famous 'Brontes', you can even go into their house and see there writing desks and clothing and furniture they used. Its worth reading up on them before you go so that you dont miss anything. Steam railway too!
A two hour drive could take you to the fantastic English Lake district (You wont want to leave)
or if you want a bit of fun, pop over the border into beautiful Lancashire and head for a day in Blackpool. i dont think you'll be disapointed.
Good Luck (Check the towns and attractions before you go by clicking on the information here on the left hand side of this page) Bet you cant makeup your mind lol)
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