I have an "old" PC running Windows 7 Home Premium SP 1 and will soon be getting a new PC running Windows 8.1.
It seems that Windows Easy Transfer is not included in Windows 8.1 and consequently, using a Belkin Data Transfer Cable for example, files and settings cannot be transferred from the old PC to the new one in this way.
I'd simply copy all relevant files to a USB memory stick and transfer that to the new computer. (In most cases that's all you need to do but you'll also need to export your browser bookmarks to an HTML file, copy that to your memory stick and then import them back into your browser on your new computer. If you use a mail client, rather than a web-based email service, you'll similarly need to export, and then import, your address book, etc).
Keep the old drive and attach it as a secondary drive on the new PC. Then when you find you need a file it's around ready for you to copy to your new chosen location.