Hillennium - S4-E10
Continuity mistake: In the episode we see the door to the boiler room (where Peggy's computer is) the door opens outwards into the hallway. Later in the episode she comes in to the room to check on some of her printings she was doing overnight. In this scene she opens it inwards. This wouldn't be possible as the door has a knob meaning it wouldn't be a two-way door.
Hillennium - S4-E10
Continuity mistake: As Peggy goes for her present and rips the wrapping paper to see it's a grandfather clock, it is set at 12:35. The following shot it's at 11:55. A little later on when Hank is about to varnish the clock, the time changes again before and after he closes the garage door where he is doing the varnishing.
Hillennium - S4-E10
Continuity mistake: Just before Hank uses the varnish on the grandfather clock you can see a quick shot of the power drill. This would have been impossible as we saw, and he told Bobby, he got rid of all his power tools the day before for some corn. Later in the scene when he wakes up the power tool has disappeared for good.
Hillennium - S4-E10
Continuity mistake: Before Peggy reads Luanne and Bobby her musing about "Noel", Bobby is to her right and the shot shows them all from behind. The next shot he is to the left of Peggy and right next to Luanne, despite Luanne having Peggy and Bobby between her at the start of the scene.
Hillennium - S4-E10
Continuity mistake: After taking some propane tanks from work, Hank comes home and starts telling Peggy to throw out her old computer. The clock in the background starts off at 10 o'clock. Hank then sees Dale knocking at the door and the time has changed to 1:50. After Dale comes in, it changes again to about 11:35.
Answer: Jeffrey Boomhauer is a Texas Ranger as can be seen in the final episode at the end when he sets his wallet down, it flips open revealing a Texas Ranger badge.