Go on the ear foundation website they do walks... or tesco for "run for life" (if i remembered correctly your dad died of cancer?) This would be good one, you don't have to run... u can walk instead if you wish.
There is a walk for life coming up for the hospice my dad went to. the walk is called midnight memories. I am also considering to do that. I may do the EF walks if there is one near me but i doubt it.