I'm assuming you're looking at a used Panda. If you're looking new, then the Panda 2012 section is the place to be. Otherwise, read on...
A lot depends on your budget, but for the mission profile you're describing one of the later 1.2 dynamic eco's should fit the bill pretty well. £30 road tax, remote locking & Aircon as standard (despite what's said in the link), and you should be able to pick up a
top-notch 2010 example privately for around £4k. What's not to like?
The 1.1 models are probably best avoided unless your budget is very limited - the engine has a lot less torque than the 1.2 & you'll need to use the gearbox to keep up with the traffic in town, so it's neither as relaxing nor as economical to drive.
Eleganza's have all the toys but cost a little more in fuel, road tax & tyres - only you can decide if the additional options are worth the extra money. The 1.4 100HP is a cheekily fun car with something of a cult following - getting a good one for a reasonable price may be challenging and it's more power & expense than most folks need in a 6000 mile commuter car. I'm admittedly biased against diesels, but the 1.3 Mjet won't save you much money in fuel over a 1.2 petrol & could expose you to some nasty repair bills if you are unlucky - one chap on here recently was looking at a £2k bill to replace the injectors at around 85000 miles. 4WD models are worth considering if you need a 4WD vehicle but will cost a lot more & decent ones are a bit like hen's teeth.
The cars are generally reliable; there have been issues with some electrical components, most notably the power steering; often (but not always) all that is needed is a battery change. As with all modern cars, if any dashboard warning lights are illuminated, it's perhaps best to walk away at the earliest opportunity.
We run a 2010 1.2 as a commuter car; it's proved to be utterly reliable in its first 30000 miles & returns around 55mpg with LadyKitching doing most of the driving
. (I reckon I could get 60mpg out of it, but that's another story
).
Alternatively, you could do what I did & pay around £3k more for an equivalent 500 & get worse seats, poorer visibility, a smaller boot & only half as many doors
.