I have an old Win XP Professional 32-bit machine. Intel Pentium(R) 4 CPU 2,4 GHz and 1,25GB RAM. When I try to install Ubuntu 14.04 from DVD I get this message: This kernel required an x86-64CPU, but only detected on i 686CPU unable to boot please use a kernel appropriate for your CPU. What can i do?
Your processor only supports 32bit operating systems.
You need to download a 32bit Ubuntu version as @Mitch stated in the comments.