It depends on the information that you need to transfer; if it is your data/files, you can use an external drive or a thumb drive via USB, or you can do it over the home network, if applicable. There is also a settings transfer utility in Windows that allows you to save and transfer your customized settings from one PC to another, so you don't have to waste time with all that setup again.
If what you really need is to transfer your entire OS installation you can use an HDD-cloning utility (something like Acronis, for instance); keep in mind that you will need to re-activate Windows because the hardware will be different in your new system (for retail Windows). For OEM Windows, you could try, but I don't think it will allow you to do that.