Delay opening Word files

I am running Windows 2000 on a networked P800 desktop. If I open a Word file by going into Windows Explorer & clicking the file, it takes about 25 seconds to load the file (this has only done this in the last couple of days & I haven’t done anything new). If I open Word (which takes 1 second) & load the file from File/Open, it takes 1 second.If I open an Excel file by going into Explorer & clicking the file, it takes about 1 second. What is happening & how do I get my response back?