A lot of times they will seem low on compression until you run them. Give it a run first and after running try to move it over by hand and you should see/feel some compression.
Jimmy Skids
I use raw fuel and my thumb. Pull the rocker arms, soak the valves down with fuel, and gently push down on the valves to get them to start moving. If that doesn't work then pull the head and soak it for a while in fuel and then work them back and forth.
Sounds like the lifters are gummed up. Pour some raw fuel down the pushrod tubes and let it set for a while. Then hold pressure on the pushrod side of the rocker while spinning the crank. They should free up. The other thing would be to send it in for a going over.