For the financial year 1 April 2014 to 31 March 2015 as you have / will be spending more than 182 days outside of India, you are Non-Resident from tax point of view.
For the period 1 April 2014 to Aug 2014, any salary / income you have earned in India is taxable and tax need to be paid.
For the period Aug 2014 to 31 March 2015 the income you have earned in Saudi is not taxable in India. You can transfer money to India or keep in Saudi, it has no effect on the taxes. Any interest income you earn, or rental income you earn, or any other source of income in India is taxable.
You would need to file returns accordingly.
An NRE Accounts allows you to transfer funds out of India without any questions. So if you intend at some point in time in future to move funds out of India [say settling down in Saudi or UK or US etc] it is advisable to have NRE account. If you are sure you don't want to transfer funds out of India, you should open an NRO account.