DSL Problems: Both Wired and Wireless

We got DSL less then a week ago, and since we did I have had nothing but problems with it. Nothing is working as expected, and the tech support from my provider is horrible; pretty much all they tell me is that it must be my 3 month old laptops fault. I don't know about that...

Problem number one: Wireless. At the time of installation, I was not home to try out my wireless access, so the installer just installed the Siemens SpeedStream router/ modem and left. Everything on the computer that he hardwired via USB cable has worked just fine, but the wireless has not. I have a 3 month old Toshiba Satellite laptop, with 512 mb RAM and 100 gb harddrive, and a built in wireless card. I am able to access the wireless internet, but the connection is incessantly cutting out. I more or less live on AOL Instant Messenger, and with the internet cutting out every other minute, communication is difficult. It literally boots me every 2 minutes at least. Every so often it lets me stay on for an extended amount of time, but for no apparent reason. I know that7 2.4 ghz phones interrupt wireless networks at times, so I disconnected the one that one, but still had problems. Similarly, I turned off our airborne satellite dish, still to no avail. I then tried changing the router's channels, still with no result. I don't know what else to do...

Problem number two: Wired. I grew tired of being kicked off all the time, so I decided to just use an ethernet cable until I got the wireless to work. More problems. My laptop is recognizing the connectionas a Local Area Network, but not as an internet connection. I have it directly cabled from my laptop to the router. On the router's configuration page, it recognizes the connection as unknown, but says it is disconnected and therefore not receiving internet connection. This problem I'm sure is just because of my networking naivity, but all the same I need it fixed.

I apologize for this message being so long, but I did want to include all of the details. I appreciate any desperately needed feedback.