Then if you want to get rid of them, make sure they aren't left outside in plain view to advertise to burglars that you have a computer. Don't fill out warranty cards, and register the product as yours, until you know the product works. This makes it easier for a retailer to take back a product that could be resold. Once you know the product works, register it immediately. At least scan it before you begin setting up the computer or turn the machine on.
Manuals give an inventory of all parts and software.
You can make sure everything is there. Have at least three boxes of blank disks on hand. When you turn on the computer, it will ask if you want to back up the files. If you have enough blank disks, by all means say yes, and feed disks as the machine asks for them. You'll thank yourself later if anything crashes.