HELP! The DSL problems have re-surfaced. :(

[Shurikane]

Recall the several months ago where I'd get disconnected from the internet for absolutely no reason. Blaming the router, I switched from a Linksys to a D-Link and then everything worked fine.

Until now.

I'll come to the computer only to find out that all my transfers are dead. I can't access any website, I can't connect anywhere, and even then, the router reports as being connected to my ISP. But, if I hit disconnect and try to reconnect, the router will keep on dialing to my PPPoE, dialing and failing for several minutes, sometimes as much as two hours, before finally making a connection again and then everything works fine. This problem has the annoying habit to come up whenevere I'm not actively at the computer - such as when I'm at school or during the night when I'm asleep.

Several points to ponder:

-If I call my ISP, they claim they can't even detect my modem on the network. Of course, they lay the blame of absolutely all internet problems on their customers unless they are doing some kind of heavy maintenance.
-I'm a full-speed Torrenter. My downloads are fruitful enough that I can get my stuff at 30 Kb/s. In fact, my Torrent downloads work so well that my mother complains her own connections time out.
-When the problem gets in there, the hardware tries to connect, thinking it's still on the network and all right. I'll end up waiting for a minute while my browser says "resolving host" or "finding site" before telling me it failed.
-When the router tries to reconnect to my ISP, I'm only given the cryptic message "PPPoE connection failed" before the thing tries again.
-What's especially frustrating is that this problem just popped OUT OF THE FUCKING BLUE! I haven't installed anything, no configuration changes, no crashes, nothing, absolutely nothing! So why is my connection fucking up NOW?!