DNS issues

I can only believe it's some sort of DNS issue that i can't seem to figure out on my ubuntu linux laptop. it's been happening on and off over the last month. Here's what i know:

sometimes there are no problems, sometimes surfing sucks.

i have a router controlling a High Speed DSL connection on my network. *when surfing on my ubuntu laptop, some sites take 30-45 seconds to completely download (open). some don't open at all and i get a timeout error. *when surfing on my iMac or Windows PC surfing is great-fast, never any problems.

*when i ping yahoo.com or apple.com (for example) from linux, i get times of 1000 ms at times (vs) the 30-40 ms i get from my windows or Mac box. *sometimes the pings on my ubuntu laptop timeout and i get errors like "host yahoo.com could not be reached" and 100% packet loss. i never get this on my Mac or Windows. *from linux; if i use 'dig' or 'host' on yahoo or apple and ping their IP addresses directly. the pings work fast and normally. *always*.

oh ya, and connecting to an internet radio station (somafm.com) with xmms, which uses the IP address of the station, it always works, *always* playing streaming music, even when i can't surf or ping to the station when these problems occur.

etc-resolv.conf: search bc.hsia.telus.net nameserver 192.168.2.1 (192.168.2.1 is my router IP address)

i'll provide more info if needed. but does anyone know what could be causing these problems on my linux laptop. and never on my iMac or Windows PC. i use mozilla and firefox on all computers. and the computers are all plugged into the same router with the same settings for all computers.

cheers.

-- Be the change you wish to see in the world. -Mahatma Gandhi