Ethernet trouble

Alright so i just got to college and i have a macbook. I plugged it into the ethernet and my internet keeps going on and off. The strange thing is that aim and other torrents will download but web pages won't. Everytime i want to change a webpage i need to change my network configuration either to BootP or DHCP. To be honest i don't even know what those are but when i change the configuration it works.

I was wondering if someone could tell me how i could fix this problem so I'm not constantly changing the configuration.