Upgrade wireless aadapter

Hi all,
I have two older computers:

Gateway 500XLS PC, P4 3.06GHz,
1Gb RAM, Windows XP SP3,
40 Gb WD HD,
40Gb Maxtor HD,
Intel Pro V10/100 net connector,
no wireless card

Dell Inspiron 8100 LAPTOP, P3 1.0 GHz,
512 Mb RAM,
Windows XP SP3,
40 Gb HD,
Intel 8255r wireless adapter.
Westell 802.11g wireless PCI card.

DLink DIR 625 wireless router.
I want to set up a wireless connection. The Dell laptop only supports WEP encryption. Can the software or drivers be upgraded to WPA/WPA2? Intel says that only Dell can upgrade because Dell added programming to the adapter & Dell doesn't offer any upgrade.
Excuse any confusion of "adapter", "connector" I'm new to this
I've set up my wired connection to the DLink router & setup a wireless network. Even after checking the box "use WPA/WPA2" the laptop refuses to connect to the net,although it can find it on the wireless connections. says it only supports WEP.

blithe.spirits