I just share my experience.
I heard my epmloyer said before, when you got employee and the daily pay is > RM 10.00, you should pay EPF.
So when we establish a firm, sure to be register first, otherwise how EPF give you majikan no. and post you the borang caruman, same as SOCSO. For income-tax, I think yes, becaused you are business ppl, when doing business sure got SSM registration form and income tax register no. also. They will post you borang E every year for employee earning detail, and your company account need to submit your annual report to income tax office also. I'm not sure will you appoint an accountant to incharge your account or not. But I know, you should submit.
You may call to EPF, SOCSO & LHDN for more detail. I think all you should register.
Last time my company also using excel to calculate the salary, as long as pay not against to labor law, is okay.