OK mine aren't really recipes because I make them up as I go along, hence no measurements!
Red (orange) lentils I like to use for soups. A favourite one is to fry chopped onion and garlic, chuck in tinned chopped tomatoes, chopped parsley, chili flakes and lemon juice, add the lentils (may need to add some water too). Simmer about 20 minutes til done.
Brown/green (continental) lentils are good for things like pies and pastas. One favourite is to make a kind of shepherds pie. Fry chopped onion, add the lentils some herbs and other veggies (eg chopped carrots or peppers), cover with a strong vege stock (Vecon is good for this, or meat eaters could use a meat stock). Simmer til done, pour into a baking dish, top with mashed potoaoes and cheese and bake for about 20 minutes.