Hi,
Regards part i) take a look at http://communities.vmware.com/thread/244631 - talks about TSO and jumbo frames. Large pages are enabled by default.
Regards part ii) of your question take a look at http://pubs.vmware.com/vsphere-4-esx-vcenter/index.jsp?topic=/com.vmware.vsphere.dcadmin.doc_41/vsp_dc_admin_guide/performance_statistics/c_troubleshoot_disk.html
Many tx