I am planning on starting a new business with an investor, initially
as a partnership type business.  From what I've learned so far about a
partnership type business is in essence all profit/loss from the
business is shared between the partners respective to their percentage
share in the company, thus only taxed once at the partners' income tax
whether withdrawn from the business accounts or not.  My questions are
as follows:

1. I am assuming that since the assets of the business are the
property of the partners that excess profits can be withdrawn at any
time as long as they are equally withdrawn by all partners according
to their percentage stake in the company.  Is this correct?

2. How do most partnership type companies set a schedule for
withdrawling such dividends from the company's funds?

3. I am going into this partnership with myself in charge of
operations and one other person as an investor, we are splitting
ownership of the partnership 50/50.  It is my understanding that as an
active participant in the operations of the company that I will be
taxed at a much higher rate than the other investor (who's sole
investment in the company is money), to cover the additional social
security taxes and medicare, etc.  Can this extra taxes on my
dividends be avoided by taking a salary?  If so, how small a salary
can I take (therefore optimizing my tax situation)?

4. How does the IRS define an "active" partner in the operations of a
company from a "non-active" one?  What's the difference in forms that
need to be filled out at tax time to distinguish the different tax
rates?

5. I've read that in a partnership type company I would need to file
an estimated tax return every quarter.  How is this done? What forms? 
How do I make a correct estimate?  How does this affect my end of year
income tax return?

6. Any other advice or information you may find that is relevant to
this line of questions.