Hi Jose,
Just thought I'd let you know that the IGI has a fairly large contingent of Lund/Lunn families living in the Knottingley and Brotherton areas, near Pontefract.
I was recently in Knottingley hunting down my Wild family, and when I saw your post I remembered seeing the name Lund before. I have checked the IGI for Lund and it came up with a Jonathan Lund marrying a Mary Canby on 21 Oct 1813 in Pontefract. This marriage seems to have produced at least 8 children who were baptised at Knottingley, but no William.

There's also an entry for John Lunn and Mary Wright baptising their daughter Charlotte on 01 Aug 1820.
Another marriage at Pontefract was between John Lunn and Mary Ann Dyson on 05 Nov 1825.
(Coincidentally, one of my Wild's married a Dyson in Knottingley in 1866).
So it looks like you may have several John Lund/Lunn's marrying Mary's at various times, so you'll have to be sure of ages etc before deciding which is yours.
I have the Baptism and burial indexes for both St Botolph's Knottingley and St Edward's Brotherton and the marriage indexes for St Giles Pontefract. If you want me to look anything up for you, just yell.

Sally