"1mb/s was enough for 3 people" No Way!
That's like high speed dial-up for each user :\
i say either demand that they fix the problem or dump them and get another internet provider.
the easiest way is to go to about:plugins (enter it in url) and disable all plugins except Flash.
edit: ok, in google chrome type in about:plugins in the address bar. It will take you to a page that says plug-ins. There you will see a list of plugins installed on your computer (shockwave...