Boosting Signal

Hey, i need some advice if you dont mind. I think the problem is that the signal strength is just not powerful enough, as i can connect to the network when the computer starts but if it drops out then i cant re-connect unless i restart, also im running at 54 mbps (should have a 108 mbps pci) but this can drop to 1mbps, with a signal strength of 30% to 12% (1 to 2 bars on the microsoft bar thing). Im also recieving more than 3 times what im sending.

So i was thinking if i upgraded the antenna on the router to something like this;
Maplin > Compact High Gain Directional Corner Antenna for Wireless Networks

and on my computer use the same one or something like;
Maplin > Wireless Network Omni Antenna 10dBi

But would this solve the problem and boost the speed to 108 mbps and boost the signal, as i would like to play on computer games online (counter strike etc.) And i dont want to waste aload of money and then find ill just need to use a wire and wire it into the router (LAN??).

Any advice or help would be very appericated.

Cheers
Phil