Yeesh, a lofty question you have. I'll try and answer some of it. First of all, no you do not need a dell case for the motherboard. motherboards come in standard sizes and should fit in most cases. Secondly - each motherboard is only compatible with specific models and speeds of processors, and they cannot have any damaged pins on them. This requires some research, but it's best to look up the processor slot online and see if you can find a match for your motherboard model. You do need a heatsink/fan, but those do come standard depending on the processor slot on the motherboard.
As far as special front connectors, any case will have connectors to their power switch, HDD light, Power LED, etc. Each motherboard will have pins specific to these connections, but again they are basically standard as in each case will have the connectors and each motherboard will have the pins. Again you will need to look up the motherboard to see where these connectors should go. PC makers have kept things pretty standard throughout the years with how parts work with each other and connect, so with enough practice and know-how you should be able to get this working.