Hold on. Mice, don't require drivers to be manually installed. Windows should automatically install the ps2 driver it needs.
Neither Microsoft, nor the Mice Manufacturer would provide PS2 mouse drivers. Its like asking a Car manufacturer to produce a how to guide on driving a car. It is assumed when you buy a car you know how to drive. And all cars are driven on the same set of rules.
The First thing to do would be to turn off your machine and plug in the ps2 mouse, and then turn it back on. PS2 is not plug and play. On boot up Windows should then initialize the PS2 mouse correctly. But it needs to be there before you turn on the PC so it gets picked up.
If its not getting recognized, then you might need to go into Device manager and uninstall any mouse entries there. and Restart your PC.
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Ignorance is not necessarily Bliss, case in point:
Unknown has caused an Unknown Error on Unknown and must be shutdown to prevent damage to Unknown.