David, there are a few things you can do.
Imagine your network is like the road network that gets you from home to work and back. How quickly and efficiently you make the trip depends on several factors and not only the type of car you drive. The roads, are there gates, tolls are any other things that impede your movement from one point to the next?
So when you look at your network, start with your SWITCH. Is it a 10/100 or is it a gigabit ethernet (100/1000). If it is a gigabit ethernet then you have a SUPERHIGHWAY.
Now what is the highest speed that each of the computers can enter this superhighway? For this you look at the network cards in each computer. If the card is a 10/100 then the maximum speed you it can put out and/or consume data is 100 or 1/10 the capacity of the network....BOTTLENECK.
If you have a wireless network, are you running 802.11b (11mbps) or g (54mbps)? Remember if you are running a g and you put a single B device on the network, it downgrades the entire network to b.
If you get the NETWORK up to speed then the only point of contention is the wireless card in you laptop; however, the data will be delivered as fast as possible.
Finally the issue of architecture cannot simple be overlooked. I have talked about that many times before and will not bore you with it!
