I was wondering, if we have a small and new non-profit organization, what is a reasonable salary/wage to start off for the executive board? (president, vp, secretary, treasurer) Also, would it be okay to pay all the executive board members the same salary/wage?

The reasonable level of pay is whatever the market requires, same as for any job. It depends on market conditions such as the specific skill sets required, the employees' experience levels, hours worked, size of the organization, span of responsibility, etc.

It is very important that the board of trustees put together a process for annual reviews of the employees' performance and salary levels for thoise positions that report to the board. For example, the board may have an executive compensation committee that performs this task, perhaps consisting of the chairman and vice-chair, and perhaps past the chairman. As part of its function this committee should consider investigating equivalent salaries at other similar institutions.