Each have a different purpose. It is not an either or situation -- you may need both.

A business plan provides the details and justification for a request for financing. It should be long enough to answer the important questions and create confidence in the reader.

Your power point presentation allows you to provide an overview of the business plan and make a presentation to a larger group.

One - on - One Presentations
If you are presenting to one or two people I would keep it informal but professional. The business plan is adequate -- the Executive Summary should provide an adequate overview of the business plan.

Larger Groups
If you are making a presentation to a larger group, a well designed power point presentation will allow you to provide a more in-depth Executive Summary. The purpose of a group meeting is to build interest and pre-sell them on looking deeper into your business plan.

I would only hand out copies of the power point presentation while I am making the presentation. Offer a full business plan for those interested following the presentation. Do not try to impress them with a fancy slide show -- unless you are a multi-media company. Let the facts of your business plan stand on their own merit. Be open to questions at the end.

They Invest In You
There is no magic in a business plan or power point presentation. Your business idea, background/skills, profit potential and growth prospects are what an investor is really looking for. In other words, do you have a reasonable chance to succeed.

In the final analysis, if all your numbers add up and your approach to the market is sound, you have a chance to get the financing you need -- if they believe in you!