I guess you have been given a number of options but it all depends on what you want the software it to do and how much you are prepared to spend. There are a number of softwares that can assist.
If you want to keep everything in House and not web based then for small businesses you can try comparing the following as a starter.
1. Sage (already recommended)
2. MYOB (for small businesses) can handle payroll, invoicing, day to day operations etc.
3. Quickbooks (simple to use) handles everything from small to expanding businesses
All packages start from basic accounting to professional.
There are also other softwares that are more tailored to the industry and can serve as a front and back office. Their more catered to your industry and aids your sales, marketing, payroll etc.
The straight accounting softwares (1, 2, 3,) can be used for any business type whilst the more industry based softwares will deal only with works carried out. so if you sold a cleaning service to (A) it would automatically update your sales ledge, expense and timesheet for workers and all that involves doing that job. The same process in a straight accounting software would required individual entries for the same process. It all depends on what you want the software to do for you.
I hope this helps