With that £105 million I certainly wouldn't give anyone any cash. Self-sustainability is key!
I'd buy the parents a new place, let them sell there's (or vice versa to avoid certain taxes) and then let them live off the profits of their current house for however long.
I wouldn't give any cash to charities. I'd set up a charitable trust and whack £30mio into it. Try to get a sensible ROI of 2-3%, and dole out the profits on a yearly basis to either my preferred charities or to those who apply. If it's 3% of £30mio on a yearly basis, that would mean giving out £9mio every ten years but still retaining the initial £30mio. I think...
Thirdly, and I'm not sure how legal this is, but I'd setup a property firm, and buy property which would then be let out to family (and perhaps friends), but with the intention of selling the property on at a profit at a later date. I.e. an investment opportunity (but with an unofficial tennant in the meantime).
Lastly, I know if I gave a million quid to my younger sister she'd have spent it within a year and have nowt to show from it. I'd encourage my family and friends to come up with viable business proposals in their current or chosen fields, and then aim to run healthy businesses off the back of it. If they're affectively living rent free, and getting to benefit from my various holiday homes (one of the first things I'd buy!

) then they'd be able to live off the profits of the businesses.
I'd also shamefully guinea pig off the back of my various friends' successes and expertise by setting up firms for them to run and expand.