As Andrew's said, you have to check which wireless standards that your netbook is currently being used to be connected to your modem, i.e whether is connected at "g", "n" or even "b", which is the slowest at present. As a matter of back compatibility, your wireless router may be able to use "b", "g" or "n". If it is already using the "g" or "n" already, try to improve the wireless reception of your netbook or try the wired ethernet connection instead.
Intel E4300 OC with 2GB RAMs,Speedtouch 585 Modem/Router and Windows XP Pro
O2 Standard ADSL2+ Broadband!