When Radio Button Is Selected Don't Validate Form

I want to achieve when first radio button is pressed form doesn't validate and when second radio button is pressed it does validate.I tried do it this way by assigning var to radio buttons an then checking that var on form submit but something is wrong:

<form action="" method="post" name="Anketa" id="Anketa" style="margin:0px;" onSubmit="if (os_podaci=1) {MM_validateForm('ime','','R','e-mail','','RisEmail');return document.MM_returnValue}">

<input name="dali_zeli[]" type="radio" id="Radio1" value="ne" onClick="window.document.getElementById('OsobniPodaci').style.display='none' var os_podaci=0; ">

<input name="dali_zeli[]" type="radio" id="Radio2" value="da" onClick="window.document.getElementById('OsobniPodaci').style.display='block' var os_podaci=1;" checked>
</form>