Some good answers but I'd definitely agree with the one person who said don't overlook soft fruit. It's typically much easier to grow then veg, which is usually annual and requires you to raise seedlings. You usually plant fruit plants once and then just prune them once a year.
Strawberries, raspberries, blackberries, gooseberries, currants and fruit trees (apple and plum) would be my recommendations.
Also, I know a lot of people think home grown tastes better but with a lot of veg (e.g. potatoes) I struggle to taste any difference. But supermarket strawberries for example are so often dodo. Bland and crunchy because the variety is bred for transport. Meanwhile homegrown strawberries can afford to be soft and are usually much sweeter as they aren't bred to last. You'll also save a lot of money compared to with veg, which is comparatively cheap at the shops.
You may also want to check out perennial veg too, of which there are a lot of options that are often overlooked. Again, the advantage is you plant once then prune/manage, rather than raising seedlings each year.
Good luck.