Netware 5.1 and W2k Explorer

I am still running Netware 5.1 and several W2k desktop, SP4. When I right click on a Netware server directory and select properties, it can take considerable time scanning the directory. All the while the Netware usage will shoot from under 10% utilisation to betweent 40 – 70% utilisation. System sloooows down. This does not happen with XP win Win98.