Wireless Router for Internet plus an ethernet cable for data transfer?

[#1]

I have just received a Thomson TG585v7 from PlusNet and set it up and am using it for Wireless Internet to a PC and a laptop. I always had the PC connected to the laptop by an ethernet crossover cable for fast transfer of data. Forgive my ignorance, but I didn't know that the Wireless Router also permits this transfer of data, albeit at a slower rate than by the ethernet cable. My question is, is it OK to retain the ethernet link for fast transfer of data or will it conflict with the router? Indeed, when I copy between machines how does the setup know which system to use if I retain the ethernet?
Thanks,
Barry

[#2]

A cable transfers at 100 mb wireless transfers at 10-54mb depending on the setup.
How does it know which to transfer by depends how you have set the ip on the cable. If your wireless has an ip say of 192.169.1.1  and you have the cable set to 10.0.0.1 then it will go via cable if you log onto the other pc's share by ip so if you connect to 10.0.0.2 the pc would know it has to go via cable.
If both ip for wireless and cable are in the same range say they are all 10.0.0.1 and 10.0.0.2 etc then it wont know and could go either way but would probably go by cable as the matrix would be faster.
You  can transfer via wireless but it will be slower if its just an odd file then the cable is a waste of time if it lots of big files then it better

[#3]

Many thanks. My cable has always been there and I use it daily to transfer everything from my main PC to my laptop so the latter is being used as a back-up for my main PC should the latter ever go down. So all I ever did was plug in the cable. It's only now that I have added wireless that it occurred to me it could use either method. Of course to transfer all I do is drag and drop on my PC desktop onto a laptop folder and it's done. So, again, excuse my ignorance, but where do these ip addresses come into it - that is, where are they requested and/or set up please?
Many thanks,
Barry

[#4]

There are 2 was to get an ip. You set it up yourself and enter in all the details you want or if there is a DHCP server running on the network it requests one from that and get a new one every time. The router runs a DHCP server by default and will issue ip to the pc's. You can check this by going to start/run type cmd press return and then in the box type ipconfig /all you will get a list like this
Ethernet adapter Local Area Connection:
        Connection-specific DNS Suffix  . :
        Description . . . . . . . . . . . : VIA Rhine II Fast Ethernet Adapter
        Physical Address. . . . . . . . . : 00-19-66-39-5D-CF
        Dhcp Enabled. . . . . . . . . . . : No
        IP Address. . . . . . . . . . . . : 10.0.0.10
        Subnet Mask . . . . . . . . . . . : 255.255.255.0
        Default Gateway . . . . . . . . . : 10.0.0.2
        DNS Servers . . . . . . . . . . . : 212.159.6.10
                                            208.67.222.222
                                            209.67.220.220
The ip address is the one that says Ip address and the default gateway is normally the router address. If you have wireless you may see 2 network cards one for the cable and one for the radio. If its all working there is no need to change anything

[#5]

Thanks again. Much appreciated. My Gateway address is 192.168.1.154 however the other IP says it is "IPv4 address 192.168.1.64 (preferred)" so does that mean it's one being given by the router automatically?
Barry