How should I process my: 1)salary, 2)dividends business transactions? what categories should I give them? eg, for dividends, there is: dividends, dividends payable.

If you're not using Quickbooks for payroll then your salary is recorded as follows: -

On the assumption you're just drawing an amount of cash for yourself as required

Debit Director's remuneration

Credit Director's loan (hopefully a liabiity)

Credit PAYE

I normally det up dividends as an other expense

Debit dividends

Credit director's loan

Amounts paid to you are then allocated to the director's loan.