Very SLOW to access homepage via IE

[NotquiteanooB]

Recently (4 days ago) I switched ISP's. Went from a DSL to Cable. My DSL modem/router combo allowed me to connect my 7 PC's. With the cable modem I require a router between PC's and Cable modem. Router is D-Link DIR-628 + a Linksys 5 port switch. I connected my main PC directly to modem and accessed IE and my homepage instantly. Now I moved the cable to the router and router to the modem and still could access IE and homepage instantly. I added each PC to the router and/or switch and accessed IE and homepages instantly. I did this one at a time for each PC. Set up router to allow portforwarding to 'emule' and another download site; from my main PC. Now the main PC takes about 30 seconds to connect to home page ??? After it does connect, I can select other sites from my 'favorites' list and they connect instantly; but if I try to link to something else from the selected favorite site; it may never connect or may take 1 to 3 minutes ??
I'm using XP Pro SP3
I rolled back from IE8 to IE7 ; no change, still slow.
I ran Malwarebytes, SuperantiSpyware, AVG. Nothing amiss identified.
I selected a different IP addy in the router for the main PC; no change, still slow.
I tried different homepages; no change.
I recycled power at the modem. No change.
Rebooted PC and Router more times than I can count.
I contacted the ISP; things are normal at their end; but they did assign me another IP address. No change, still slow on the main PC only. The other 6 PC's connect to homepage instantly.
What has happened to IE in my PC ??? Is there a TCP/UDP port setup for IE or specific to ISP's ??
After a very long delay, I found the 'work offline' had popped on. I toggled that off again, but still slow to connect.
I may try to connect the main PC back to the DSL setup and see if it is still slow.
I the meantime .. if anyone knows what I'm missing, or has an answer ... please respond ..
I will update after trying the DSL setup.

 

[NotquiteanooB]

UPDATE: I connected back to the DSL system and the IE connects to any homepage selected INSTANTLY !!
Problem must be in the router or ISP. Probably the ISP, because the other PC's still connect instantly. Or, maybe the router, because the other PC's aren't included in the port forwarding.

 

[NotquiteanooB]

Now permanently back to my DSL provider ... (Telus)
Shaw Cable ISP could not satisfy me with 4 calls to their Cust. Serv. Tech dept. Mostly they blame the router, without hearing the fact that it works just fine through the router to the DSL modem! The price was going to be nice ($10) per month for a year. I saved almost that much by returning the router to Staples and the modem to Shaw. Telus DSL modems are a combo router with Wireless.
I never did figure out why only my main PC couldn't connect to homepage quickly.