Yahoo has as a result of offering the free 100MB mail box, an unprecedented amount of traffic.
in addition there is talk of a DOS against Yahoo last week.
all these may have contributed to your slowdown.
in addition there is also the possibility that you have a lot of unneccessary programs starting when you boot.
you might want to login to Yahoo mail, key in user ID and change your password.
I did this late last week as a result of the slowdown in mail.
let Yahoo generate a new pw for you, login in and change it back to what it was.
this usually helps.
YOu may also want to read this article regarding start up items.
hope this helps.
please post back if further information is required.
finally since you are running behind a router, go to the router website and refresh your MAC address.
Its been 3 days now, and I am unable to get into my yahoo mail account. I would be able to get to the screen where I would enter my Login, and Password, but once I hit summit, the process bar at the bottom would just keep on processing. After a long minute, it would just bring me to an error page, at first it brought me to Internet Optimizer, and it would say like: "help/navagation error dns r dsn" and say could not find server mail.yahoo.com. I have spybot, internet organizer pro, and Ad-aware on my laptop. All the computers in my household seem to have the same problem since we are connected by a router. I use internet explorer 6.0, and windows xp. Someone suggested I download spy sweeper and scan. I did, I saw I had a Trojan called 2nd-Thoughts. I erased it along with other adwares, and it seems that my computer is even slower, and I still can't get into my Yahoo mail.
Please help. It's getting pretty frustrating.