Don't know if this is any help fitty but the same thing is happening with my dad. He knows his parents names and posibly some of his grandparents but thats it.
He has no details of marriages , cannot remember when they were born/died.
The only thing i can think of now is to go to a large library that has the St. Catherines indexes for the years 1901-1983. I know there is one at Lincoln Archives ( my nearest) , but not managed to get there yet.
Good Luck
Best wishes
Pauline