Your original code had:
curs.execute("INSERT INTO Books(Category,Title,Author,Year_Purchased,\
Comments) VALUES(?, ?, ?,?,?)", (vCat,vTit,vAuth,vYear,\
vComments) );
and your new code has:
curs.execute("INSERT INTO Books(Record,Category,Title,Author,Year_Published,Comments)\
VALUES(NULL,?, ?, ?, ?, ?), (Record,Category,Title,Author,Year_Published,Comments)");
Do you see the difference?
(Also, you don’t need the semicolon at the end of the line.)