To check how good any machine is for gaming you need to know:
CPU: I recommend intel i5 or higher at this point
GPU/Video: Intel grapics suck for gaming. Needs discreet video card. Most import part.
RAM: Should have 4 gigs+, but you can add ram later.
Display: The resolution is important info. If it's a high res display, you need more power to play games at it native resolution. You can always play at lower res, but if you bought a big nice monitor, it's nice to have enough power to use all of it.
Hard Drive: Isn't nearly as important, but SSD/Ram drives open things superfast. Spinning Hard drives are 7200 or slower generally, but shouldn't affect game play really.
If it doens't have discreet grapics/video card, it's onboard vid and will not do gw2 very well. Better to get an i5 with discreet video or even go AMD since there seems to be a lot of cheap amd laptops with ati vid (they own ati). Check deal sites to get the most bang for your buck. Fatwallet, slickdeals etc. Laptops go on sale all the time.