It will most likely be a crappy Dell brand mobo and it will not be very good or compatible. The reason why they don't tell you about the mobo or the power supply is that they are so **** that they don't want to put you off.
Ah, fair enough! That does make sense.
With regards to the CPU, will an Intel Core 2 Duo E6600 be sufficient? I enjoy multitasking (alt+tabbing when I shouldn't, etc) and running RTS, strategy and RP games mainly. Basically, what I'm asking is, will this processor do everything I want it to do smoothly?