Help-Anyone had success setting up Asus WL-300g AP? (Newbie)

I have struggled with an ASUS WL-300g Access Point and a Dick Smith
PCI 802.11b card which is on a Windows98 SE PC. The PC sees the AP
when I do a "Site Survey" but connect fails. I have also tried an Asus
WL-138g PCI card on a Windows 2000 PC with similar failures.
I am sure it is my lack of knowlege that is the problem but can't figure out what I am doing wrong. I have set up an SSID, Encryption = none,
Authentication = "Open System or Shared Key". I have tried fixed IP
addressing on the Windows PC as well as DHCP.
Any ideas? Pointers?

Can you access the AP through a WEB browser, either wirelessly or through a NIC and RJ45 LAN cable? Are you also able to use the software that came with your WIFI PCI card to check for a connection. Also is your card set to ADHOC or INFRASTRUCTURE? When you set the IP address to manual was that on both. I think the manual setting for the AP is 192.168.1.1 and subnet 255.255.255.0 and for your card 192.168.1.x where x is a number between 2 and 254 and subnet 255.255.255.0. How many PC's are you running on this AP wired or wirelessly?