[CentOS] Edit to change startup from SMP to not so SMP

>
> Ok, it was grub, and this is what I have......  I see default=0 how should I
> change that to one of the items below????
>
> Thanks,
>
>
> default=0
> timeout=5
> splashimage=(hd0,0)/grub/splash.xpm.gz
> hiddenmenu
> title CentOS (2.6.9-42.0.2.EL)
>         root (hd0,0)
>         kernel /vmlinuz-2.6.9-42.0.2.EL ro root=/dev/main/root
>         initrd /initrd-2.6.9-42.0.2.EL.img
> title CentOS (2.6.9-42.0.2.ELsmp)
>         root (hd0,0)
>         kernel /vmlinuz-2.6.9-42.0.2.ELsmp ro root=/dev/main/root
>         initrd /initrd-2.6.9-42.0.2.ELsmp.img
> title CentOS (2.6.9-34.0.2.EL)
>         root (hd0,0)
>         kernel /vmlinuz-2.6.9-34.0.2.EL ro root=/dev/main/root
>         initrd /initrd-2.6.9-34.0.2.EL.img
> title CentOS (2.6.9-34.0.2.ELsmp)
>         root (hd0,0)
>         kernel /vmlinuz-2.6.9-34.0.2.ELsmp ro root=/dev/main/root
>         initrd /initrd-2.6.9-34.0.2.ELsmp.img
>
>
>   

the top one is zero therefore if say you want to boot the third kernel 
then change default to read default=2