Transmission

So on my dads truck.  He was having this issue where when the truck would
start the first thing in the morning it would take about 30 seconds before it
would move once it was put into gear, we would put it in drive but if you hit
the gas it would take about 30 seconds before it could move.  That lasted
about a week and then on his way to work he got off the highway at his exit
and came to a stop at the light and when it turned green, the truck wouldn't
move, never stalled or anything, just wouldn't move.  So we had it towed
home.  Read all the codes and there were none related to the transmission
(a couple related to a cylinder 3 misfire which we know we need to replace
the coil)/  Checked the transmission fluid and it was fine, correct level and
not burnt.  Kept reading online and stumbled on that the pickup tube could
have fallen out, so we dropped the pan and checked the pickup tube (all fluid
was fine when we examined it), which was fine.  Replaced the filter and the
filter for the cooling lines along with the o-ring and gasket, put it all back
together and still the truck will not move.  

Some other symptoms that we noticed.  There is no resistance on the
column shifter when we move it from Park to Reverse or Drive.  Truck goes
into Neutral and will roll forward and backward.  Also noticed some damp
spots on the bell housing of the transmission, but unsure where that fluid
would have been coming from.

My current thoughts are that something is messed up with the torque
converter, but would the entire thing be shot or is there a solenoid or
something electrical that would be causing this.

Any help would be greatly appreciated.  Thanks!