we have a Janitrol Hpt 18-60 thermostate that reads as followed:

Y=yellow wire
G=green wire
R=red wire
O=blue wire
w2-white wire
E= no wire connected
C=no wire connected

We are trying to hook up a hunter which we thought would work because the person that came out said we had a one stage heat pump.
The wires on the Hunter 44155c reads as followed:

G
RC
RH
Y/O
W/B
Y1


How do we hook this up because I have no clue what each wire in our old box is used for?

I have attached a Picture of what it looks like now!

First of all, I wouldn't use that Hunter thermostat. I probably replace more Hunters than every thing else combined. Get a Honeywell or White-Rodgers thermostat.
The fact you have a connection to W2, indicates there is back up or auxiliary electric striip heat. Unless you live in a very warm climate, it would be very unusual not to have electric auxiliary heat.