2pc network running very very slow!

I just setup my brothers pc and sony laptop using a crossover cable and i am able to to use the shared folder and printer sharing, but to send a 12mb file takes about 5 minutes
Even to send a 1mb jpeg takes forever! on both computers if i click on the network icon in the bottom right of the task bar its says both are running at 100mbit.

I think the problem may be that on both computers it is unable to get a IP address will that make a diffence as they dont use a router or broadband modem just a direct cross over cable?
Will setting the main pc as 192.168.1.1 and the lappy as 192.168.1.2 help?is a ip address needed to network 2 together?

Thanks jenks trainee networker.

1. on both computers goto dos and type 'netstat -e' and see if you have a number of errors, anything above 0.01% of your packets send/recieve or so is not good.

2. On both again goto your network properties, select configure and then the advance tab. You are looking for something that might be called "media type" or "linkspeed & duplex", but you should reconize the default option of "autodetect" or "autosense", change it to be 100/full.

Thansk smokeys me brother came round to see me last and i change linkspeed & duplex to 100/full, hopefully it may of helped.