Slow to open database on Win 2000 network

[heffo]

My wifes small work office runs a Windows 2000 network, using M/S Sequel Server on the server, which feeds a booking database to 3 office Pc's running Win 2000.
The router is a Netgear FVS318 and it is working at intermitant speeds.
Sometimes the database opens in 6-7 secs, which is acceptable, but sometimes 17-20 secs to open. What could be causing this slowness?? All PC's within 5 metres of the server, and they all seem to have their share of slow access?
Any help or suggestions welcome. Should I be looking at server issues, router settings, or what.

[confus-ed]

... Should I be looking at server issues, router settings, or what.

So how well does it work if you just wire it straight in ? (assuming you have a x-over cable laying around), that might 'simply' eliminate any router issues

20 seconds compared to 7 sounds just like 'somethings' busy ..