These may well help you, but you will need to access the doc's at Treasure House, Beverley to see what they actually contain to further your research.
zDDBD - MISS L BIRD'S DOCUMENTS (FAMILY, ESTATE AND BUSINESS RECORDS OF THE BEAUMONT FAMILY OF BEVERLEY)
DDBD/52/96 17 Dec 1807 Copy deed of trust for benefit of creditors relating to lands at North Cave
1) Thomas Wood of North Cave gentleman
2) Henry Bell of Spaldington, John Bell of Portington and Edward Blyth of Belby gentlemen
Property: farm with 47 acres; 3 cottages; closes called Rees Close, Breck, Hill Close and Sandhows; Low Hall and Low Hall Garth (occupied by Marquis de Villedueil); 4 messuages and cottage in North Cave. Furniture, goods and chattels of Thomas Wood
This one could be the father to Thomas Wood, in same papers as above
DDBD/52/94 18 Sep 1790 Copy of probate copy of will of John Wood senior of North Cave
Bequests: wife Ann; son John and Thomas; daughters Ann, Elizabeth, Mary and Sarah
Property: North Cave, Elloughton, Brantingham, South Cave, Saltmarsh, Eastrington
Probate: 21 Dec. 1791
This could be a sister to Thomas Wood, in same papers as above
DDBD/93/122 19 Jun 1816 Copy will of Sarah Wood of North Cave spinster
Bequests: brother Thomas of North Cave land surveyor; sister Elizabeth Blanshard; nephews and nieces John and Sarah Garlick, Sarah Stather Stamp, John Stamp, William Wood Stamp, Edward Blanshard Stamp, Elizabeth Margaret Stamp, Kesiah Lesley Stamp, George Jabez Stamp, John Frederick Francis Wood, Ann Maria Wood, Ann King (late Blanshard) and Ann Turner (late Garlick)
Property: furniture and silver
Witnesses: John Hilton of North Cave surgeon, William Dinsley of Howden clerk to John Peirson attorney
This could be a brother to Thomas Wood, in same papers as above
DDBD/52/95 30 May 1803 Copy will of John Wood of North Cave gentleman
Bequests: brother Thomas; friend Mrs Mary Bonner alias Sketchley alias Collins (residing with testator as housekeeper); sisters Elizabeth wife of George Blanshard, Mary wife of John Garlick, and Sarah; mother; grandmother Stather; etc
Property: Plate, North Cave, Elloughton, Brantingham, Brough, South Cave, Saltmarshe and EastringtonThis Will above maybe available to download for a small fee from National Archives...
Death Duty Registers. Abstract of Will of John Wood, Gentleman of North Cave, Yorkshire. Proved in the Court of York. July 12 1804 IR 26/426http://www.nationalarchives.gov.uk/documentsonline/details-result.asp?Edoc_Id=7459730&queryType=1&resultcount=30
This could be a brother to Thomas Wood,
zDDGD - GRAY, DODSWORTH AND COBB (LATER GRAYS), SOLICITORS, YORK
DDGD/1137 14 Aug 1790 Extract from the will of William Wood of North Cave gentleman
Executor: brother John
Beneficiaries: all real estate to brother John Wood
Witnesses: James Smith, Thomas How, George Gale
Will dated 16 Nov 1784
Probate 14 Aug 1790
With copy codicil to will of John Wood, North Cave, gentleman, 30 Nov 1791:
Property: land at North Cave, Brantingham, South Cave, Saltmarshe and Eastrington
Beneficiaries: devise of cottage at North Cave to wife Ann for life and then to eldest daughter Ann Wood
Witnesses: William Blyth, Matthew Langrick, John PeirsonWith copy declaration as to pedigree and marriage and death certificates, 1840
Regarding the titles of Sir & Lady, not found anything relating to him as Sir Thomas Wood. Her title of Lady would have come about from his title if he was granted this first, otherwise he would have had the title or Lord bestowed upon him at marriage as she would have been a Lady by birth etc.. I think looking at the doc's above he was a gentlemen first and foremost and somehow became "Knighted" for some reason and therefore his wife became Lady Wood.
You mention that Sarah Wood was a dau of a Captain, I don't think this would make her automatically a Lady, so I think this title came from Thomas Wood, I wonder if Sarah's father had a hand in him being "knighted" and him becoming a Sir
Maybe there is a register for all those that receive Knighthoods etc.. Now I stand to be corrected upon my understanding of the above as it takes a little sorting out from how one is addressed by these titles depending on how they came about them initially
Regarding the birth of Ann Maria Wood c 1807, she may well have been born South Cave, but her birth would not be registered, reg was from 1837, only a baptism would be registered as such and may contain details of her birth date and place, so maybe you need to be searching afield, she could also have been baptised privately at someone's private chapel etc..
Does Thomas Wood appear on census info for 1841/51/61 and if so where and what was his profession???