Blocking Safari, etc.

Hi there,

Recently, I purchased a Mac Mini for use at our business as the point of sale computer. Personally, I've been a Mac for years now, but this is the first time we've put a Mac to use in our business.

We've had problems in the past with extraneous internet browsing on our computer, etc. This was all on a PC, and it was easy enough to block internet browsing by requiring a password.

My problem now is, how do I do essentially the same thing, but on OS X?

We tried creating separate login accounts, but this created a problem when using the Quickbooks program.

Any ideas?

As always, thank you for any help!