How can I apply node template file only to node view page but not revision page?
I don't have a D6 site around with revisions enabled so I can't test this, but the following code should disable the custom template for the revision pages:

function MYTHEME_preprocess_node(&amp;$vars) {
  $template_name = 'node-content-type-name';

  // Work out if we're on a revision page
  $on_revision_page = arg(0) == 'node' &amp;&amp; is_numeric(arg(1)) &amp;&amp; arg(2) == 'revisions';

  // See if the rogue template file is available as one of the suggestions.
  $template_index = array_search($template_name, $vars['template_files']);

  if ($on_revision_page &amp;&amp; $template_index !== FALSE) {
    // Remove the rogue template file from the suggestions.
    unset($vars['template_files'][$template_index]);
  }
}