When I bring up the web-based config on my desktop PC (brand new, very fast, no malware/viruses) that is attached via LAN, it takes a about 10 seconds to load each page, from the login to all the sub-menus. When I log into the web-based config via my laptop (which is about 5 years old and pretty slow) via wi-fi everything loads instantly. What could be causing the slowdown on the desktop unit? The desktop is running Win 7 and the laptop Win XP. The laptop loads the config fast in IE, Firefox and Chrome, the desktop is equally slow in all 3.

It is just the router config that is effected, loading of web pages etc on the desktop unit is fast as expected.

Edit: Some strange results when I ping the router:

Pinging 192.168.1.1 with 32 bytes of data:
Reply from 192.168.1.1: bytes=32 time=38ms TTL=255
Reply from 192.168.1.1: bytes=32 time=1ms TTL=255
Reply from 192.168.1.1: bytes=32 time=1ms TTL=255
Reply from 192.168.1.1: bytes=32 time=1ms TTL=255

Ping statistics for 192.168.1.1:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 1ms, Maximum = 38ms, Average = 10ms

Edit: Strange. Removing ZoneAlarm stopped the ping anomoly. But still, the web-config takes ages to load on my PC and is instant on my laptop, despite me pinging normally <1ms on my PC.