However, I notice all three of those are TN panels, and two of them are LED-backlit - are you aware of the blue tinge that LED backlights can cause? You haven't specified a budget yet, but you might consider the Dell U2211H, which is an e-IPS panel.
I don't think you can get a PVA or IPS monitor in that price range, so the LG Flatron W2261V-PF (the third of your links) is a good choice - it uses a CCFL backlight (which gives better appearance compared to a cheap LED backlight), and it has the resolution and inputs you need.
However, saying you'll use your old 1680x1050 monitor as secondary gets my attention. I haven't done multiple-monitor setups myself, but I've read in other threads that multiple monitors with different resolutions can be problematic.
I'm a little confused that your budget range is in euros, while the preferred website you list has prices in pounds, but the Dell U2211H is available at Overclockers UK for £229.99 (equivalent to €263.343 according to xe.com), and the HP ZR22w is available for £221.66 here: http://www.porthale.co.uk/products.asp?partno=VM626AT
i've had the opportunity to use my 1600x1200 20.1" and my 1920x1080 40" as primary and secondary. you cannot stretch the taskbar across both but other than that there is no real issue.
if you want to save money go with the TN panel, just be aware that if you are not right in front of it you will get a greying of the image (think laptop screens) which is why I like the other types. if this doesnt bother you then a TN panel will be fine.