FWIW, using an "n" type wireless router (Rosewill with 3 good antennas -- under $30 on special sale) and "n" dongle (multiple makes/models in the $20 range) works throughout our house -- 110ft x 80ft x 3 levels (max dimensions) -- transmitter (WiFi router) centrally located on the middle level. Other folks, bringing their "n" WiFi devices (e.g. their laptop or e-book) into our house have easily used them far from the transmit point for bi-directional communication.

Prior to going "n", we had "b/g" -- the reliable range on b/g was less than 30ft (through thick walls) even with the "largest" after market antennas at both the transmit and receive points. As you indicate, network cards with small antenna's did not work reliably at 30ft with b/g.

I am assuming the subject application only requires a range of about 30 feet. Thus, as the OP indicates, b/g works -- albeit slowly -- hence the request for a faster solution. "n" should have no problems using decent dongles at such close range (if b/g already works), in my experience.

Anyhow, since "n" with dongles was such a cheap/easy solution for us in a large house, I could recommend it, in general. What I can't do easily is tell others how to hook up such a router to their specific "modem". I also cannot guarantee that the laptop in question will accept a dongle on top of its own internal WiFi.

I've got a dual N band router, but the issue I'm talking about isn't the distance---it's interference. Your neighbor 2 houses down might be picking you up fine, but in certain areas of your own house you may have issues due to sources of interference.
The only way to find out is to try it with the devices you want to use. You can't assume that a wireless network that works at one house will work just as well at another house. They're all a little different.

I agree

I think for PowerLine, Both Terminals have to utilize the same Breaker Group/Circuit.

So, If upstairs and down stairs are on separate circuits (which going by residential building code they better be), the powerline wouldnt work, as it only sends the signal on the local physical circuit, and not back through the breaker box and to another circuit in your home.

If you have another router, you set one up to be a wireless access point / gateway. So You'd Have Modem-> Router A-> Router B Set As Access Point -> laptop.

Interfearance may be an issue, as My parents house they put their router in my old room which is in the far end of their house, and between my room and the living room/den is a long hallway,. with a closet that has the Gas water heater, the Electric Heat Pump and all that crap, not to mention countless other appliances that give off a pretty nice size EM field (as they cause image distortion on my parents old old CRT TV.)

That's the big downside to powerline adapters is they both have to be on the same phase or leg. One room may be on the other phase or side and it won't work. They also don't work with any kind of surge protector. I did successfully make mine work though. Ran a powerline adapter from my 2Wire router/modem and in the other room across the house another PL adapter and a Dlink router. Works fine.