We're having 'Praise my soul, the King of Heaven' and 'We come, dear Lord, to celebrate'. The second one is to the tune of Dear Lord and Father of mankind. The words are more modern and perfect for just after the vows. Here's the first verse -
We come dear Lord to celebrate
the love our friends have found,
and thank you God for their embrace
the joy and promise in this place
which makes it Holy ground,
which makes it Holy ground
If anyone wants the full words just let me know - the words are perfect and not overly holy if you know what I mean!