harley: Oh and as for the game for teh PC upstairs, you can take your harddisk out, take it upstairs, connect it to the MB of teh other PC, copy the file from that Harddisk to that of your kid's PC and take the harddisk back to its original place.
Ali mentioned a good solution too. With WniRar you can split a big file into smaller zipped files, then you can copy them all onto a disk, or several disks, and copy them to your second pc, and when you want to unzip the files, the program will automatically ask for the second part of the splitted file after unzipping the first, then the third, so on.