Internet Help IP(com Cast)?

Ok so December 12 2008 Com-cast came over to install "Digital Phone & Voice" its suppose to be this awesome great thing...so far its been shit connecting to internet. The phone is working great and my desktop computer works fine but slower then normal, the problem is the internet wont seem to hook up to work with my IBM laptop everything is hooked up to a D-Link for those that don't know it splits the the Ethernet net jack for multi jacks 4 to be specific. so anyway..when i hook it up to the laptop it shows that its trying to connect but then it stops after 1 or 2 mins and show the icon for limited or no connection after i saw this i went to the cmd and brought up the property's for the IP and what popped up was (for security purposes im not going to reveal any of the real ip numbers or anything that could compromise my computer)
Connection-specific DNS Suffix.:
Autoconfiguration IP Adress...:156.212.123.44
Subnet Mask.........................:233.233.0.0
Default Gateway.....................:
and then when i bring up my desktops config it shows everything filled.
can anyone help?
thanks