1) We know it's Win98se...but that's it.
2) What's the rest of the system? How much memory?...What's running in the Start-Up ?
3) Run task monitor (resource monitor) , check memory usage..watch it deplete resources
4) Is it a new addition ( the printer )
5) Check for driver updates for it, if you're using the original ones...if there is ( maybe a full set up routine ), remove it from both your hardware (device manager) and software(add-remove program)