Blocked when copy/pasting text from the threads!?

Hello to all of you!

Before starting I should mention the line up: WINXP Prof SP2 updated till 09/2006, Firefox 2.0.0.1, Modem-router Zyxel Prestige 661H-61, AvastHome up to date.
My problem is this and I do not know if it is mine or the site's, but it is very weird non the less, as I have not heard it before, nor it has happened before to me:
I have downloaded and installed CPF about two months ago, but I had problems with Azureus and utorrent and because I could not get them to pass through CPF, whenever I used them, I closed CPF (I know it was a mistake, but I could not find another solution at that moment). Then I found this forum and started reading it. I thought it would be a good idea to copy/paste the content of FAQ and Help threads to MS Ofiice 2003 for future reference, so that I will not have connect to the internet every time I needed something. You may say that new things are added every day and that I need not do something like this, and you would be right, but I like all the information of one thing to be in one document. In the beginning I came as a guest and it happened after I copy/pasted the text of one thread, then firefox could not load any other page and I mean any other like Yahoo! not just from inside the forum. I thought it was my connection but I noticed that Itunes radio worked fine so I said maybe it's firefox's problem. I closed FF and cleared all the private data (Ctrl+Shift+Del). I opened it again and came back as guest once more, copy/paste and again the same thing. The next time I signed up and did it again, same results. What is happening? Should this thing happen? I will add that it happened when I copy/pasted, the contents not the title of the thread.

Sorry for being so lengthy but I wanted to add as much detail and background as possible to help identifying the problem, being mine or not.
Thank you in advance.