replacing inline javascript with jquery

greetings Newton21205 , , , the code in your javascript is way too OLD, and out of date, as you have tests for things that in year 2017, that do not even exist any more -

        else if (navigator.appName=="Netscape"){
            NS6=parseInt(navigator.appVersion)>=5;
            NS4=4>=parseInt(navigator.appVersion);

these tests for "Netscape" are not valid, as "Netscape" no longer exists, , . .

In my view, Your best bet is to abandon that old javascript code, and start over with code that is more current, and corresponds to the HTML and Javascript standards used in browsers today.

Also, you can use non-Jquery, plain javascript to eliminate the "Inline" HTML javascript used.

Also your code seems incomplete - as you have it it does not make sense. You have script that refers to checkboxes in MainForm but the checkboxes exist outside of any form - there is also "onlick" code wandering about by itself outside of an element.

done