Crumbs, I've gone from being an insufferably ignorant drama-queen noob to being asked for my advice in the space of about 20 minutes! I feel as if the captain of the football team has just asked me to take off my glasses and let down my hair.
All the major supermarkets deliver as far as I know (Tesco, Sainsburys, Morrisons, Asda), I've even heard of people having food deliveries to random parts of the canal ("please be at this bridge in this post code at this time"), the drivers'll do pretty much whatever you ask them to (within reason) - and in fact, every driver we've had has been a cheerful delight, I keep expecting a grump to turn up eventually but it hasn't happened yet - you can go out to their van, they'll carry the stuff to your boat, you go back and forth carrying and they'll help you etc. Yes, it's very easy.