What components do you have...?
I hope you've figured out that HD0 and HD1 are your hard disks...
We'd need to know CPU to guess which of those is likely to be it. Just have a look in the bios to see what temps are what, although if you have C n Q enabled, then the bios CPU reading will be higher than the reading in Windows, as it'll be running at stock multiplier in BIOS, and lowest in Windows (assuming you're idle...)
The 2 is probably a screwed sensor, or miss calibrated in some way.
The 51 is probably chipset/NB temperature if you're running an NF4 board.
Pretty hard to figure out what you've got based on temps alone, and I don't know Pentium Dual Core voltages to be able to figure whether you're running a X2 or a Pentium of some sort.
Seems that the two Temp1's would be CPU, as they're both roughly the same...
Meh, I don't know.