Fruit bushes

I don't think the majority of raspberries would be happy in a pot because it is their nature  to spread.    However the new variety Glen Coe is a possibility but I don't know if it lives up to the catalogue description.  The autumn fruiters tend to crop a little at a time over a long period. 

In any case the yield would be low from such a small area. 

Bluberrys might be a good choice as they grow well in large pots but you need to remember to plant them in ericaceous compost. Plant them in 46CM pots or similar and don't let them dry out especially in dry weather. They don't seem to be bothered with cold weather as mine have just started growing after the extreme cold winter. You may need to net them as Blackbirds like the fruit when ripe.

Hello, Fisherman makes a good point so I thought I'd weigh in here with a link - http://www.jparkers.co.uk/plant-0004292-ca-1/blueberry-top-hat/

It's a small blueberry for only £2.99, bit of a bargain! It may not be the prettiest specimen I suppose, but if a pretty blueberry is what you're after then Homebase are doing Jamie Oliver blueberries (don't ask me why JO is sponsoring blueberries), for about £7, and they look to be maybe 2 years old and nearly ready for fruiting.