The e-smith installer should automaticaly detect that you're running an SMP motherboard and install the relevant kernel and modules.
Lilo will default to booting the smp kernel after install but when the lilo screen comes up at boot time you'll also be able to select 'esmithup' which uses the uniprocessor kernel and modules in case you have problems.
I'm currently running SME 5.1.2 on a dual Pentium Pro motherboard with no problems whatsoever...
Gary