Our family has several restaurant concepts under operation. For our older restaurants, my mom uses Peachtree on a PC to do the books. I'd be surprised if they didn't offer a MAC version as well. I've also used this software personally, and found it pretty easy to master with just a basic understanding of generally accepted accounting principles. Quickbooks seems more popular these days though, and I have not used that software. I can say that the times I had problems with Peachtree, their tech support was very helpful.
A second option is to hire a bookkeeper. The firm we use charges us $500 a month per restaurant, and a reasonable fee for filing our corporate income tax return at the end of the year. $500 is very very good value to me when weighed against the amount of time I would spend each month processing payroll, paying invoices, compiling P&Ls, etc. As an added bonus, they take care of my personal return each year for free.
Another benefit of hiring an accounting firm to handle the books is that if there is ever a problem with a return, they are your first line of defense against the IRS. The IRS can make your life hell for a while, even if you are trying to play by the rules. If you file your own tax forms, any mistakes you make are completely your responsibilty, if you use an accounting firm and have a problem, at the very least you may have grounds for some sort of malpractice suit to recover your damages. This is, of course, assuming the data you provide to your accountant is true and accurate.
If you decide to pursue the accountant route, make sure you get a good one. They should be Certified (CPA), and I would talk to other local small businessmen to see who they use and recommend.