What would happen if I connected two of my PC's together with a network lead even if one is Vista and one is XP. Does anything happen and are there any advantages. I don't have any software just a five metre lead and wondered what would happen if I did it. Thank you for any advice.

If you want to connect 2 PCs then you need a cross over cable. Looks like a LAN cable but is a little different. One advantage is that if one computer is connected to the internet, you can turn on 'internet connection sharing' and the second PC will also be able to access the net.

Cable only costs a couple of dollars.

As CD said, a cross-over cable is best. Some LAN adapters can sense what cable is used and cross-over internally, check with your computer/adapter manufacturer - don't just try it blindly as older adapters can be damaged.

Beyond that there is the nightmare of getting XP and Vista's security 'features' to talk to each other Chok Dee on that....