My new Wireless router is doing my F*****g head in

The situation is I want this sucker locked down tight as possible but the fediddleing XP is driving me nuts.
Unit is a Linksys and I am using a Linksys PCMCIA wireless card in my laptop. I want my laptop and only my laptop to access the router by wireless.
So I went in to the router set up, changed passwords, disabled SSID broadcast, limited IP's to two (one for desktop and one for laptop) and set access restriction to my PCMCIA card Mac address only. All good so far ...........
So on to Encription etc. According to the manual WPA is the new "thing to use" and so I duely followed the instructions to set security to WPA, TKIP and a keycode which was no prob on router setup. So mosey down to laptop and network has disappeared which I expected. I went to the configuration for the network connection and set Access to WPA and the other box to TKIP but the boxes to enter the keycode are greyed out

.
Ok read PCMCIA manual - ahhh need to download an XP Patch for WPA - ok downloaded and installed.
Still no go - boxes for key remain greyed out
So I delete the home network from the lower window and try to add it manually - no go. Now however it recognises the network as a different one
So delete ALL networks from the wireless networks list and try to manually add my known good home one (being especially careful to enter the correct SSID) Nope - nadah.
Back to deaktop - back to setup on router - re-enabled SSID broadcast and voila - network back visible.
Please please can anyone tell me what is going on ??????????
I am sooooooooooo sick of computors so so so sick .......... All I want to do is what it says I can do on the box - is that reallt too much to ask ?????????????????