different temp reading?

[Kalsar]

i just bought a celeron D 420 1.6 @ 2.2 and i use stock hsf. it goes like this:
bios: ~26C
everest (cpu diode): ~49C
speedfan: theres temp1 and temp2 (dunno whats up with that) and no cpu temp.
motherboard: ~32
which one is correct and why cant i use speedfan? thx