Wireless Networking

[Santaclauseee]

Hi guys,
  right my house is set up with a wireless networking, NETGEAR 108Mbps router, 108MB usb card, and my laptops onboard intel 54mbps card. and i was wondering why when i transfer files the speed of my network drops to less than 2mbps? i've tried diffrent channels, diffrent speeds everything. so is there anything i can do to speed this up?
Also security, does it effect speed at all? and onboard the netgear router it has a security device that only allows selected mac address to access the router, is this sufficent enough?

Kind Regards
Ben

[ctjoyce]

1st: Transfer speeds dropping whilst transfering large files over WiFi when you have two different speeded cards isn't uncommon.

2nd: The MAC filter is sufficent enough. Should you feel that you need more security a WEP password will do the trick.

Cheers
Cameron