Hoping for some hints n tips for a Lake Garda holiday

We are going in May next yr, for a wedding.
which is being held in Malcesine Castle on a Saturday afternoon.
So the plan is to fly over on the friday hopefully,
stay in a hotel the fri and sat nights ( possibly Hotel Castello)
Then stay elsewhere for the rest of the week ( it will be May half term )
What is the easiest / closest airport to fly to ?!
is it doable if you don't hire a car ? what are transfers / public transport etc like ?
Any days out / things to do you recommend ? we have 2 boys who will be 14 and 8 and there will be lots of other children from various friends and family, ranging from 10 months - 16 yrs ish.
I am hoping to use Tesco deals for the weeks accom, with Individual Travellers
or could hold out and see if we get a SUN holiday, to one of the Lake Garda sites :
Europa Silvella
Fontanelle
San Vito,Cisano
Bella Italia,Peschiera
Butterfly
Del Garda,Peschiera
Any hints,tips and info you could give me would be a great help
Have never been to Italy so looking forward to it
Thanks in advance

xx