PAE is Physical Address Extension
, which is nothing to do with SMP.
PAE was designed to allow the cpu to access more than 4GB of RAM. (on 32 bit systems - 64 bit can already access more than 4GB)
This means programs only need to worry about accessing normal memory space, because the PAE maps memory higher than 4GB into a 32 bit accessible addresses.
SMP is multiple CPU support.
Some distros include PAE by default these days, but you have got it anyway.
A benefit of PAE is that it supports the NX bit
which is a security method to prevent malicious programming.
Editing grub wont change uname, because uname queries the kernel version.
The SMP is because you have more than one physical cpu or cpu core .
If you really want to stop having the benefits of SMP, then you can edit the kernel parameters in grub.conf and put
at the end of the line. Both of those will disable the smp code.
(allegedly - I haven't tried it because I have a dual quad core system, and why pay for extra cpu if you are going to disable them ?)