I am running a Linksys WRT54G Wireless G Router with D-Link Wireless PC Cards in 2 laptops. With a little research, the installation is relatively easy and there are lots of info on the web for encryption. I have been posting a few questions this week regarding my signal dropping and just by chance, I was reading thru other posts and I think I fixed it by changing the channel signal that my router works on.
I run XP Pro and Win98. I use a cable modem thru my cable provider. When I first installed the setup, I went thru the install as instructed and it seemed pretty complicated, but after reinstalling my system recently everything actually plugged and played since it was already set up before.
The only thing that takes getting familiar with is the encryption for security. It is pretty easy. Either use WEP with encryption keys or WPA with Pre-Shared Keys. WEP encryption keys is a string of letters and numbers that are generated from a passphrase (password) that you think up type in and the router software converts into that string for you that you have to type into your PC card utilities to grant access to the wireless router. WPA is something new that I just changed over to and is supposed to be stronger and with that you just type in a passphrase to grant the access in. you just have to make sure that the setup on the router is the same as on the PC cards or else no connection. There are a lot of screens to get thru and you just have to be thorough. There are other security things like MAC filters and firewalls also.
When I was researching wireless for my use, I was told that unless you have good encryption and security, then your data.network is wide open for the world to see if you get hacked into.
This is my first wireless system and I am pretty happy with it. The router cost me only about $79, the pc cards were like $54 and $38 (based on the Version type B or G) all at amazon.com.. The Wireless G router can work with both G and B type pc cards.