for nvidia drivers, you could just use the drivers from the nvidia site.
Easy to install, only real "trouble" is if you ever decide on compiling a new kernel, you have to reinstall the nvidia driver!
Xen= Xen™ is a virtual machine monitor for x86 that supports execution of multiple guest operating systems with unprecedented levels of performance and resource isolation.
PAE= In computing, Physical Address Extension (PAE) refers to a feature of x86 processors that allows for up to 64 gigabytes of physical memory to be used in 32-bit systems, given appropriate operating system support. PAE is provided by Intel Pentium Pro and above CPUs (including all later Pentium-series processors except the 400 MHz bus versions on the Pentium M), as well as by some compatible processors such as those from AMD. The CPUID flag PAE is assigned for the purpose of identifying CPUs with this capability.
My source: http://en.wikipedia.org/wiki/Physical_Address_Extension
Kdump= Kdump is a kexec based crash dumping mechansim for Linux. Kdump functionality is broken mainly in two components, user space and kernel space. Kernel space patches are already part of main line kernel tree. User space component is nothing but a patch on top of existing kexec tools.
And you should use a i686 installation!
Hope this information helps you on your way to installing FC6.