Most Receipt printers should be pretty easy to install and come with a good Windows driver. The Star TSP100 is one and the Star printer should be pretty easy to install and setup. And as soon as you have the driver installed you should be able to print to the printer from Windows.
However sometimes we see problems are issues where unplugging and plugging the printer cause Windows to get confused and you will see a couple of drivers in the Printers list (Copy 1, copy 2, etc.). If this happens the best way to fix this is to turn the printer off, delete the printers in Windows and then turn the printer back on. This will re-install the printer. Right click the printer and choose printing properties and then perform a Windows test print. If this works, then it is very simple to setup RetailEdge.
To setup the printer in RetailEdge:
Choose Settings | Workstations from the Tools menu.
Modify the workstation you are setting up.
Press the Receipt Printer Tab
Choose Tape Style - Via Windows Printer Driver
Select the Printer Driver you just setup.
Select Star TSP 100 or Star TSP 200 from the Devices list.
Save the Settings.
And you should be good to go.
One other thing that we sometimes see is that there is an old instance of the printer in the list that RetailEdge is trying to print to. It can sometimes help to rename the Windows Printer Driver something like Start TSP100 (New) so that when you select this Driver in RetailEdge you are sure you are selecting the correct one and not an old one that was previously installed.