[rentagas]

The main problem with the stores you mention is they usually carry stock in out of town warehouses not the stores and they will not have a clue about specs other than what is written on the price card.

Most LCD screens will accept a VGA input, they often do not accept a input of the screen resolution but will stick to a VESA standard resolution/refresh rate to improve compatibility and will scale to that resolution (ie 1280X1024). If they are widescreen that may make the picture look odd (stretched). Some will accept a maximum resoltion picture but only via HDMI-using a DVI to HDMI converter.

Choose a screen in stock, ask to see the manual and check the resolutions in the specs in the manual. If necessary take your lap top with you and set it up in the store. Whataver you do don't believe a confabulating currys salesperson.