The Peugeot seems a decent car and has quite a strong likeness to the old Saxo. Pugs are certainly popular — about every tenth car on the road round here seems to have a lion rampant on it. The only thing putting me off is the mileage. I looked on AutoTrader for 306s with over 100,000 miles, and it currently has 52 (although a good half of those lie between 100k and 110k) with the highest one a whopping 172k miles (2.0 litre engine) and the next at 157k (1.4 litre). The one at Humphris isn't even that expensive in comparison (it's on page 2 of 6, and there's some optimistic person out there expecting £3995 for a 1.8 Cabriolet with 109k miles).
The only thing going for the Suzuki is that it is very cheap (with a low insurance rating and a high mpg to match). However, the reviews say that it's dull, dated, not much fun to drive or to ride in as a passenger, comes with damn-all safety features and requires maintenance every 6000 miles which is about half what other manufacturers specify. It also has a tiny engine (I'm not sure how that '4' crept into the poll, as it's a 1.0) and the car looks slightly bigger than the 1.4 Saxo so I can imagine it feeling very sluggish to drive. And in contrast to the popularity of the Peugeot, I saw maybe about three Suzukis on my 4.5 mile cycle to work this morning.
The Mégane is a decent car, but as the_muttster points out, it seems a lot more expensive than a comparable Citroën Xsara. (He found one in Abingdon which I am in two minds about, but I would need quite a lot more details than that listing provides before I decided to go for it.)
The Rovers are overpriced and expensive to insure. Nevertheless, the 416 could be a good buy with a few quid knocked off it and a decent warranty, and if it lasts a couple of years then it's cheap enough to scrap if it goes wrong.
Of course, if I don't buy a Citroën then it won't find favour with smallclanger, who wants an "up-up" on the front radiator, and moreover I might not be allowed to visit buzzy_bee's place in future. ;-)
e: There's a green Xsara 2.0 HDi SX in Amersham; more expensive but only 53k miles and comes with 12 months MOT and 6 months warranty as standard.