Hello, I am Keith, one of the experts on Just Answer, and pleased to be able to help you with your question.
How were you taxed on an ISA? The whole idea of an ISA is that they are tax free.
When you moved to Indonesia did you send a Form P85 to The Inland Revenue. If you did not then you should do so immediately, but now, of course, to HMRC. On receipt that Department will classify you as non resident. On return to the UK advise HMRC in writing. Fortunately there is no time limit as to the submission of P85s, it is available on the web and can be filked on line.
Moneys inherited in the UK are not taxable. Any Inheritance Tax (IHT) will have been paid by the executors or administrators before distribution.
Endowment insurance products are generally tax free on maturity or surrender.
I think I have covered everything. Please follow up on this thread if there is anything you do not understand.