I have a Danby as well. I'll post a link below to a very helpful site with all the details regarding what I'm going to say.
First, the Danby is worth what you paid for it. Of the inexpensive kegerators it is the one I prefer. I have two and the Danby is superior.
Having said that though, I have done several modifications which I recommend to you.
The biggest one is the temperature controller is notoriously bad. I replaced mine with a Johnson digital.
Next, a lot of the beer foam issue is because the beer in the tower is warmer than the beer in the keg, consequently the co2 comes out of solution too rapidly. I bought a unit off of ebay (but you can make one) that is simply a box fan with a hose which takes the cold air from the bottom of the kegerator and circulates it up into the tower, keeping the beer in the tower the same temp as the beer in the keg,
Next, I got a Minkota digital fishing thermometer, ran the wire into the Danby and into a large beer can filled with distilled water. This way I am measuring liquid temperature not air temperature - they are sometimes wildly different. And BTW, pay no attention to the temp. reading on the front of the Danby.
Finally, get (if you don't already have one) a good, quick reading digital thermometer that is used for cooking. Calibrate it by putting it in ice water to check if it is accurate. If it shows 32* it is accurate. If it doesn't, note how much it is off and figure that into any future measurements. I say this because it is ultimately BEER temperature that is important.
Oh and one more thing. If you are not already using a chart like this one:
http://www.kegerators.com/articles/carbonation-table-pressure-chart.php Use it to set the psi on your regulator. The pressure of the co2 must be set in relation to the temperature of the beer.
No One MORE thing. Check the length of your beer lines. frequently they are way too short. 5 to 10 feet is good. What happens is the beer comes out too fast if the beer line is too short, resulting in a glass of foam. In my Danby I have a 5' beer line and a 10'.
Here is the link I mentioned above:
http://www.micromatic.com/forum/us-en/kegerators-kegerator-kits-home/6587-danby-kegerator-improvements-part-ii.html
Good luck. I have pictures if they would help.
Steve