Pinging the server; internet speed

Let me begin by wishing you a Merry Xmas and a very happy better year.

My internet connection comes from a antenna on the roof wired to my pc; Since quite some time my internet connection became really slow; too much time to open a webpage;

I pinged the server and here's the result:
Reply from .............................. time=1951ms TTL=64
Reply from .............................. time=378ms TTL=64
Reply from .............................. time=1166ms TTL=64
Reply from .............................. time=747 TTL=64
(sometimes the time get over 3000ms)

I think that the delay (those ms) are the reason behind my low internet connection; Am I right? pls advise; I need to know what to tell my ISP so that he betters by connection.

Thank a lot