Choice of stove on a BR20 or other open boat depends on how much cooking you do. If you just want a brew-up, go with the Trangia. The back packers cook set has a great, well shielded kettle but choose the gas burner or multi-fuel version, not the alcohol burner. (Meths burners are efficient but burn dry without warning and, if you spill any meths when re-filling, like as not you will set your trousers afire sooner or later. )
If you are cruising in a dinghy, not just day sailing from pub to pub, you will want to do some proper cooking ...and that means proper pans. Backpackers need ultra light gear so Trangia pans etc are thin aluminium. They heat up quickly (saving fuel) and cool down even quicker. The only thing that is good for is fresh mussels, a stir fry or maybe something in a tin. Baked beans, ready made stew, cook-in sauce and other abominations. Try anything more ambitious and it will stick and burn. Get some decent, heavy pans especially for the boat, don't pinch them from your kitchen but - most important, this - use them at home first to season them. Try out your recipes before you go sailing, too.You don't want to mess about when you're cold and hungry.
Serious pans need a serious burner. Paraffin pressure stoves churn out the most heat but who wants paraffin on a small boat? Everything aboard will reek of it inside 5 minutes! I use two of the stoves shown in the photo. The cheap one shown costs less than a tenner and a posh stainless steel model will set you back around £30. They are stable, give an easily controlled flame, have piezo-electric ignition and pack away in a neat case. You can't pack them away dangerously hot as you have to reverse the trivet to shut the case. The cartridges are relatively expensive but self-seal so no need for a vented gas locker. I never cook or eat in the cabin, always in the open cockpit. This avoids problems with condensation, carbon monoxide and spillages caused by passing ferries. Cook under the spray hood if it's raining. (The only serious fire I've seen on a dinghy was caused by an attempt at a fry-up in the rain. The rain sinks to the bottom of the cold oil and when it heats up and boils, oil is splattered everywhere.)
What to cook is down to personal taste and common sense ...and the limits imposed by your ability to clean your pans and dispose of waste without polluting the boat or the environment. e.g. Use rice, not potatoes. (No peelings to dispose of.) I have a score of well tried recipes which I'll post on my blog ...one day.
I have to agree with Jonno in one respect. There are plenty of waterside pubs serving food and good draught beer so don't cook if you dont have too!