In theory, there's no vegetable better than the red pepper for bringing Mediterranean sunshine to a dish, but the majority of red peppers on sale in Britain are the thick-skinned glasshouse-grown "bell" variety. A combination of growing method and variety means they are full of water. So roast or grill them to drive it off and concentrate their sweetness; try not to add any more liquid ingredients. If you have the time, leave red peppers at room temperature for a day or two to dry out and darken in colour; this improves them.
More elongated, thinner-skinned romano/ramiro variety peppers have a shade more of the taste profile you get in chillies, but without the piquant heat. They are the closest in flavour you'll get to those voluptuous, curvy red peppers on sale in southern European and Middle Eastern markets.
Why are peppers good for me? Red peppers are one of the best sources of the red-coloured carotenoid pigment, lycopene. Some studies suggest that eating lycopene-containing foods could lower the risk of prostate, pancreatic and cervical cancers. They are also ideal for topping up your store of two other carotenoids, lutein and zeaxanthin, which are naturally found in the retina. Some research suggests that eating foods rich in these pigments can help prevent macular degeneration, a condition that can impair the vision of older people.