Is this someone trying to hack my site
 

This error was emailed to me, is this someone trying to hack my site:

Database error in vBulletin 4.0.4:

Invalid SQL:
INSERT INTO talkangl_donation_paypalipn (
`txn_id`, `userid`, `test_ipn`, `notify_version`, `verify_sign`,
`first_name`, `last_name`, `payer_business_name`, `address_name`,
`address_street`, `address_city`, `address_state`, `address_zip`,
`address_country`, `address_status`, `payer_email`, `payer_id`,
`payer_status`, `business`, `receiver_email`, `receiver_id`,
`item_name`, `ip_address`, `quantity`, `invoice`,
`memo`, `tax`, `option_name1`, `option_selection1`, `option_name2`,
`option_selection2`, `payment_date`, `parent_txn_id`, `txn_type`,
`payment_type`, `payment_status`, `pending_reason`, `reason_code`,
`mc_gross`, `mc_fee`, `mc_currency`, `mc_handling`, `mc_shipping`,
`settle_amount`, `settle_currency`, `exchange_rate`, `case_id`,
`case_type`, `case_creation_date`, `valid`
) VALUES (
'', '0', '0', '0', '',
'', '', '', '',
'', '', '', '',
'', '', '', '',
'', '', '', '',
'', '', '0', '',
'', '0', '', '', '',
'', '', '', '',
'', '', '', '',
'0', '0', '', '0', '0',
'0', '', '0', '',
'', '', '0'
);;

MySQL Error : Duplicate entry '' for key 1
Error Number : 1062

No, it is not a hacking attempt but a db error. That comes from a custom mod I think, try to ask at its own thread about this.

It appears as though you recently installed an incompatible PayPal Donations modification.
Without knowing anything beyond the clues in the posted error, I would suggest you first disable your PayPal donations modification via the AdminCP Plugins &Products Menu and see if perhaps the mod has been updated, quarantined, replaced, or such.