Bvlgari Aqva is definitely the best on the list. Live Jazz has a good opening but then it gets a little herbal for a hot summer day. I wouldn't wear the others in any season, but that is my personal choice. 1 Million would be a more than a tad overwhelming for Summer and Cool Water is played out.
I guess Cool Water would be pretty decent in the Summer - but maybe the summer of twenty years ago,
Aqva would definitely be my choice - but it may get cloying in the Summer so you may want to look at Aqva Marine, which is much lighter but still quite aromatic - or even the new toniq versions of both scents that are coming out this year.