You could use an external hard drive to move files and folders, or (depending on how many you have), store them online opposed to locally on your PC using something like SkyDrive (you get this with Hotmail/Live email accounts), Dropbox etc.
In terms of removing the data - simply 'deleting' something does not make it completely unretrievable.. If you have anything of a particularly senstivie or personal nature, I would ask someone that you know who is tech-savy to format the hard drive for you. If this is not an option and you are not going to be selling or giving the computer to anyone, you can actually just destory the hard drive - you can smash it to 1000 smithereens or pay a data disposal/tech company to destroy it for you.