OR condtion in drupal 7

That's not correct, the default is AND. To use or, you need to use:

$or = db_or();
$or->condition();
$or->condition();
$query->condition($or);

Upload images in drupal 7

$form ['boxthird'] ['thirdcontentlogo'] = array (
'#type' => 'managed_file',
'#prefix' => '<div class = "row-fluid">',
'#suffix' => '</div>',
'#description' => '<p style="font-size:12px"><span class="icon-hand-right"> </span>  Uploaded Inner logo Image Size should be 165 x 61 pixels. </p></span>',
'#upload_location' => 'public://sitefiles/',
'#default_value' => isset ( $gethomestaticdata ['boxthird'] ['thirdcontentlogo'] ) ? $gethomestaticdata ['boxthird'] ['thirdcontentlogo'] : ''
);




 if ($form_state ['values'] ['kitphotos'] != "") {
$validators = array ();
$dest = file_default_scheme () . '://sitefiles/';
$file = file_save_upload ( 'slider_image', $validators, $dest );
if (is_null ( $file )) {
$file = file_load ( $form_state ['values'] ['kitphotos'] );
$file->status = "1";
$fileobject = file_save ( $file );
$buffet_img_fid = $fileobject->fid;

// file usuage
$fileusuage = new stdClass ();
$fileusuage->fid = $fileobject->fid;
file_usage_add ( $fileusuage, 'file', 'mediakit', '111' );
} else {
$file->status = "1";
$fileobject = file_save ( $file );
$buffet_img_fid = $fileobject->fid;

// file usuage
$fileusuage = new stdClass ();
$fileusuage->fid = $fileobject->fid;
file_usage_add ( $fileusuage, 'file', 'mediakit', '111' );
}
}