Small Engines (Lawn Mowers, etc.): front wheel and tire on an old Murray, air compresser, cotter pin

Question
I am a little (easily) confused about your answer to Gail concerning her Murray front wheel where you said to remove the cotter pin and then the wheel but to take it to a dealer.  Is the dealer to remove the tire from the wheel?  I don't have that problem because the tire has completely fallen off the wheel.  It did this before several years ago but the friend who fixed it with an air compresser then is no longer in town.  Would this indicate that I must have a new wheel, especially since I didn't notice it and mowed on it for who knows how long?  I have a small yard and the mower gets very light use but does have to do some twisting and turning and reverse.  And if I take this wheel off by simply removing the cotter pin, can I get it or another back on correctly without too much difficulty since I am no longer mechanically inclined.  I really appreciate your answer and hope I havn't used too much bandwidth with my ?.

Answer
Jeanne
I don't think I answered this question before, then again we get so many questions. I will try to give you a answer.
If the tire went flat and you mowed on it for a while you will need to see if it is damaged in any way.The reason you should take it to a dealer off the mower is that it will not cost you that much and it will be less hassle than taking the whole tractor. To put the wheel on the front is very simple,there should be washers and a cotter pin look at the other wheel and install it the same way.