checkboxes not aligning with their labels in firefox

when i view the page containing checkboxes - in firefox the checkboxes and their labels are not aligning correctly(they are not in one straight line)..the labels seem to appear a bit below the straight line in which they need to appear..this behaviour is only when i view the page in firefox ..it appears fine in IE..similarly with radio buttons also..

Any information in this regard will be very helpful..

Thanks