I can help you with who not to use!
actually in my past 3 roles, I have gotten there at the implementation of an HRIS each time!
1/ CHRIS
2/ Peoplesoft
3/ Spectrum Plus - ADP
They all have goods and bads. Peoplesoft is big and expensive, but very good, it is no good for payroll though. CHRIS does
HR and payroll pretty well, but you have to get used to all the abriviations (they may have changed it now, but when I put it in, it was very key focused, not windows style), Spectrum Plus does the job fine, for both.... but the service, support and consulting is an absolute mess. I would never go there again.
Good luck!!!