login page is gone after nextgen gallery reset

Hi,

The site can still appear with these on top of web page:

Warning: fopen(/home/stylewish/public_html/wp-content/plugins/nextgen-gallery/nggallery.php): failed to open stream: No such file or directory in /home/stylewish/public_html/wp-includes/functions.php on line 4198

Warning: fread() expects parameter 1 to be resource, boolean given in /home/stylewish/public_html/wp-includes/functions.php on line 4201

Warning: fclose() expects parameter 1 to be resource, boolean given in /home/stylewish/public_html/wp-includes/functions.php on line 4204

If go login page:

Warning: fopen(/home/stylewish/public_html/wp-content/plugins/nextgen-gallery/nggallery.php): failed to open stream: No such file or directory in /home/stylewish/public_html/wp-includes/functions.php on line 4198

Warning: fread() expects parameter 1 to be resource, boolean given in /home/stylewish/public_html/wp-includes/functions.php on line 4201

Warning: fclose() expects parameter 1 to be resource, boolean given in /home/stylewish/public_html/wp-includes/functions.php on line 4204

Warning: Cannot modify header information – headers already sent by (output started at /home/stylewish/public_html/wp-includes/functions.php:4198) in /home/stylewish/public_html/wp-includes/pluggable.php on line 1196

how to fix it so that I can login? please advise, many many thanks!!