Netgear WG111v2 Frequent Disconnects From Wireless Internet

I am using a desktop with a Netgear WG111v2 dongle to connect to my cisco linksys router.Basically my old modem died which was connected to a wireless router so we replaced it with a cisco linksys router and ever since the change ive been having difficulties connecting to internet on my desktop where as the the rest of the laptops in the house have had no problem. In the begining the desktop would always say its had limited connection the the network and such i couldnt connect to the internet but disconnecting the router several times and restarting the computer several times eventually the computer would have full internet access through the network without disconnecting at all.

A few days later the computer starting connecting to the network and gaining full internet access usually without turning of the computer and restarting it although i would disconnect from the internet every now and again for a minute or so and reconnect automatically this would happen more frequently when using Skype or msn messenger extremely frequent when using skype and especially when in a call.ive updated the driver of the wireless dongle to the latest version.my desktop is running vista while the laptops are running windows 7 and mac osx or whatever.ive also download a free version of avast and given a full scan of my computer without finding any threats.