Button variables problem

hi guys,

Im trying to get my head around actionscripting…and this is what i have so far…but its not working as i want.

what im trying to do is make the button frame go to frm2 when its clicked and in so doing, it makes the _root goto the respective label. how can i tell the other buttons (mcs) to stay at frame 1 when one of the other buttons are clicked?

var is new for me…am i setting it right?

code inside button container mc:

var C=0;
tbtn1.onRelease = btn1.onReleaseOutside=function(){
    if ( C=1)
            delete btn1.onRelease;
            btn1.useHandCursor = false;
    else if (C=0)

also, how can i add a rollover functionality that does not break the other commands on the buttons (ie: stop at frm2)