Without seeing code it's hard to give you the solutions.. But heres the list of depreciated functions being used and the recommended switch.
ereg(); // Switch to preg_match();
split(); // switch to preg_split();
Your warning:
Warning: Cannot modify header information - headers already sent by
(output started at /home/stockton/public_html/g1/Version.php:41) in
/home/stockton/public_html/g1/lib/lang.php on line 356
You have output prior to issuing a header();
Your other warning:
Warning: strtotime() [function.strtotime]: It is not safe to rely on
the system's timezone settings. You are required to use the
date.timezone setting or the date_default_timezone_set() function. In
case you used any of those methods and you are still getting this
warning, you most likely misspelled the timezone identifier. We
selected 'America/Chicago' for 'CDT/-5.0/DST' instead in
/home/stockton/public_html/g1/Version.php on line 41
Add this at the beginning of the page:
date_default_timezone_set('America/Chicago');
Alternatively you are using Gallery v1.. To take out the heartache of having to re-code another API, upgrade as @dagon said.. Upgrade to gallery3
All this can be found and double checked by reading your depreciation/warning notes and using php.net or stackoverflow to finding a resolution to these problems.