I know this is like years old post but since there is no selected answer I hope this answer may give you what you are expecting...
if(document.getElementsByTagName){
var table = document.getElementById('table className');
for (var i = 0, row; row = table.rows[i]; i++) {
//rows would be accessed using the "row" variable assigned in the for loop
for (var j = 0, col; col = row.cells[j]; j++) {
//columns would be accessed using the "col" variable assigned in the for loop
alert('col html>>'+col.innerHTML); //Will give you the html content of the td
alert('col>>'+col.innerText); //Will give you the td value
}
}
}
}