As PPs have said, growing vegetables is a hell of a lot of work! An established rose bed is much less hassle, so that’s definitely not a swap to make if you don’t have a lot of time and you don’t like gardening.
My one piece of advice is don’t rush in and start ripping things up before you’ve lived with them for a bit (I’ve always done this with houses too, despite only ever buying fixer-uppers - the ideas you have before you buy a place always change and adjust once you properly understand what you’re dealing with).
If you don’t know much about plants, check which ones will give you the most bang for your buck (established, low to no maintenance, soil/climate appropriate therefore don’t need loads of extra watering etc) before you make any major decisions. This will mean living with the garden for a year and seeing what it does. A lot of the structural shrubs and bushes will more or less mind their own business, and the stuff that’s highly labour intensive will start to shows signs of neglect if you’re not tending to it, so you’ll know those are things you need to move on to new homes.
Definitely offer established plants to other gardeners via freecycle and FB - you’ll have no trouble getting rid.
At the end of the day you need to create the space that works for your family, but in your situation I’d be trying to end up with a garden that’s still beautiful and established as well as practical. Lawn is great for kids, but is almost moribund when it comes to supporting wildlife and the environment, and still requires maintenance.