Site Crashed-Jetpack Plugin

I have resolved it.I just deactivated all the plug ins from phpadmin and the site came back to life.

Yeah, I have accessed your site, I think you are having the same problem.
Follow the instructions below.
All the best.

Login to your cPanel and open the phpMyAdmin interface.

In phpMyAdmin, find your WordPress database and download a backup copy by using the ‘Export‘ function.

Back to your database. Find the wp_options table and press ‘Browse‘ button under the ‘Action‘ column.

Now, all rows under wp_options table will be listed. Find the row for active_plugins option. In my case it was table row no. 38.

Press the ‘Edit‘ button for your active_plugins row. Now you will get an insert form with option_id, blog_id, option_name and option_value. Under option_value you will find something like this:

a:13:{i:0;s:19:”akismet/akismet.php”;i:1;s:43:”all-in-one-seo-pack/all_in_one_seo_pack.php”;i:3;s:36:”google-sitemap-generator/sitemap.php”;i:4;s:33:”most-commented/most-commented.php”;i:7;s:23:”tweetmeme/tweetmeme.php”;i:10;s:27:”wp-pagenavi/wp-pagenavi.php”;i:12;s:15:”wp125/wp125.php”;}
Those lines represents your active WordPress plugins. Delete all of them and save your edit by pressing the ‘GO‘ button.
That’s it. Now all your plugins are deactivated. Login to your WordPress admin area and activate the required pluings again. Just be careful not to activate your problematic plugin again. Also for stability and security reasons, it is advised that you remove all your old and unused plugins from your server.