A licensed copy of Windows XP with an OEM key is typically restricted to the original Dell computer it was sold with, making it illegal to install on another PC. Users have reported that attempting to use the OEM key on non-Dell machines results in activation failures. If the Windows XP disc fails to boot, Microsoft offers a set of boot discs that may help. For those considering alternatives, Windows 2000 can bypass activation codes, but this method requires additional steps. It's important to check if the Windows copy has an OEM designation, as this indicates it is tied to the original hardware. If the key is not OEM, it may be used on another computer, but running both systems simultaneously can lead to key invalidation. There are also discussions about exploring free operating systems, such as Windows Essentials 2, as viable alternatives to Windows.