You can't beat a good divertion!
On a similar idea....if possible, introduce a very small gathering (family) around the guests of honour and 'play the occasion down'....but then lead them to the waiting reception! SURPRISE!
As for 'fun' during the evening, OTT big name badges and spoof 'This is your life' or 'Mr & Mrs' style themes can be a great larf.
'Characters' from soap-land with short 'lines to read' to the audience can be amusing.....it can bring out the most amusing and comical antics.
Short and sweet is ideal....not to drag. This way, whatevr you do in a 3-5 minute slot can be very memorable after the hello's and greetings / half way into the proceedings.
Novelty Spoof all-time-favorite songs - Prodigy, Sex Pistols, Mrs Mills, Je Taime, Sean Paul, etc can crop up during the night for ongoing giggles.
Scenes from films....(add wigs and imagination)....Grease - You're The One That I Want, Dirty Dancing - Time Of My Life, Singing in the Rain....beware of water splash!!!
Produce a sheet for a game of Twister and threaten to expose 'the skeletons in the cupboard' of who was the 'Twister champions of yester-year'.
Limbo is great for everyone to participate in, old time musical sing-a-long (where's yer curly tash Esk?) advert singalongs (Murry mints, Fairy Liquid, etc) if you want to be alittle cheeky.
Or - forget all that and become a Chippendale for the night.
There is nothing better than the family occasion to have a great time. Hope it goes well.