I was in my 20s in the 80s and learning to cook the day to day stuff as well as set pieces. I remember a few little brown wholefood and vegetarian recipe books. As well as Delia (my Bible), I had Claudia Roden's Middle Eastern cookery book, all Elizabeth David's cookery books, some Jane Grigson, some Rose Elliott and assorted other vegetarian cookery books. We weren't vegetarian but didn't want to eat nothing but meat. The range of fruit, veg, pulses, spices, herbs etc was increasing all the time.
What you cook for an 80s meal depends a lot on what your intention is. If it's to make everyone laugh you'd go for half a grapefruit for starter, vol au vents filled with M&S tinned creamed chicken or frozen chicken kiev, Viennetta for pudding.
But if you want something that works as a good menu, try these:
Avocado and prawn cocktail, including iceberg lettuce, which was new to the UK in the 80s (or so I've just found out via Google) - avocado was very novel, prawn cocktail was very popular
Pork chops with cream and mushrooms - she's updated this recipe a bit from the 80s version, no bad thing, ordinary cream did split but it tasted delicious
Fresh fruit salad including kiwi fruits, a great novelty in the 80s - this might be the moment to add Viennetta on the side! Or cheesecake, which I recall being extremely popular back then.