PCI card or wireless dongle

[bigjimmyauk]

Never used one on a desktop PC i've always used wired,

Got the kids a small pc to internet browse and do homework and need something wirless to connect to my virgin router (d-link DIR-615)

needs to pass through 2 walls and cover about 25 Feet

Got windows XP and a pentium D

So which should i get?

 

[edscdk]

Dongle with a USB ext cable, a lot include them, that way you can place it for best reception if there are issues