Ive been sent a refund from a website and the transaction has been stuck on unconfirmed for a while. Is there anything I can do to get it to confirmed faster?
The transaction fees spiked significantly in the past few hours; that's why that transaction is still not confirmed. You can use CPFP to get your transaction confirmed faster.
Here you can find good step-by-step instructions for Electrum. You might be able to do it easily by right-clicking on the transaction in the "History" tab and selecting "Child pays for parent" option.