Best Practice for Setting up Partitions and LVMs

I'm installing Oracle 11gR2 on RHEL v5 which will live on a VM in vSphere and I want to optimize performance the best I can by setting up various directories such as /tmp, /var, /opt on separate hard disks within the VM. Will the OS install give me the option to do this and I'm wondering how others have set this up for a better performance.

I'm new to LVM and not sure how to best set this up as well, so I'm looking to see what others have done or if someone could point me in the right direction.

thanks