The cabin crew will serve drinks and dinner and normally yes, they will dim the lights to allow people to get some rest if you wish. There's nothing to stop you watching a film or sitting at the bar however - I like the VS1 if you have a short journey on arrival.
On the return, you're cutting it fine IMO. If you have any delay you'll be struggling but at least if you get off quick and leg over to VS then the terminal isn't busy so you can get checked in and through security quickly. Hand baggage only will be a considerable help, as would printing off your own BP.