First, don't invest all your lifesavings, leave something just in case. In fact, if I were at your place I would invest at max half of this sum and the other half I wouldn't touch.
You can choose some prosperous altcoin, like ethereum and you can risk with some shares but for that consult some broker first.
Ethereum can be a good choice just like what the saying is, don't put all your eggs in one basket. But it's also good if you want to hold 5 bitcoins for long term. And invest into reputable casino's to their bankroll's, actually there's a lot of good place to invest your bitcoin you only need to look for legitimacy.