1. ASA inside connects to Cat 6500 Switch.
2. Cat 6500 switch has all servers connected to it.
a) should the inside of the ASA map to one of the vlans on MSFC i.e. same subnet.
b) Secondly, if there is FWSM placed after MSFC, should the outside VLAN of FWSM be the same vlan as mentioned in point a) i.e. the inside of the perimeter ASA.
No they could be the same if you wanted ie. you could have
ASA - FWSM - MSFC
but it really does depend on what you are trying to protect with both your ASA device and your FWSM. It can also make a difference if you are using other service modules in the 6500 such as a CSM/ACE module for load-balancing.
Perhaps if you expand on your requirements i could point you in the right direction.