I'll not worry that you have no text in your submit button but go straight to the mod_rewrite code.
RewriteRule ^items-([0-9]+)-([0-9]+)-([^/\\.]+)-([^/\\.]+)$ items.php?dler_id=$1&ctgry_id=$2&page=$3&choice=$4
First, kudos to you for understanding enough to NOT use the dreaded (.*) to match garbage.
Second, no Last flag?
Third, you do not need to (therefore, you should not) escape the dot character within a character range definition.
Lastly, on the assumption that you only use the .htaccess in the DocumentRoot (here, that's localhost), your leading start anchor is ignoring the folder in your URI and is, therefore, failing to match your URI and performing the redirection.
Only the last "error" (failing to account for the folder in your RewriteRule) will prevent your code from working. Hint: deleting the ^ will have the same effect as implementing this code for every subdirectory else add folder/ after the start anchor. If your .htaccess is within the folder directory, then you may need to add a leading / - I'd make that /? as subdirectories handle the leading / differently and I'm too tired to remember if it's required here or not.