Wirelessb card and Wireless G router

I have a laptop that has an integrated network card built into it and it is an 802.11b card,but I have a wireless G router hooked up to my desktop so that my laptop can pick up a wireless signal without hooking it up to the router's LAN cable. Does having a wireless G router and a wirelessb card effect the speed at all?
Anyways, my question is I am getting 54MB/s as a connection, but the other day I was picking up an unsecured wireless network from next door and the closer that I got to the home the stronger the signal and the faster the speed. I got the laptop download speed up to 120MB/s as well as the surfing speed. That was off of an unsecured network at that! My question is can I boost my laptop speed up to that much just picking up the signal off my wireless g? the strongest that I have gotten is 54MB/s. Don't get me wrong the signal and speed are pretty good, I am just wondering why I was hitting 120MB/s the other day and I only get 54 off of my wireless network in the other room

If somebody has any answer please respond I would really like to know!


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Wireless26