MarMema, pay no attention to that website. It is NOT official Catholic teaching, and it's considered really far-out by the vast majority of Catholics. Please don't judge all Catholics by this fringe element! You can find all sorts of really kooky stuff on this site! It's like judging everyone in Illinois by the Jerry Springer Show.
As for Fatima, the Blessed Mother didn't say "convert" she said "consecrate to her" and "pray for" -- big difference!