Firefox problem

Hi.
I have 2 problems with my Firefox.

1) I have set Firefox to load the tabs that I had open when I closed it, as soon as I re-open it.
But it doesnt. When I open Firefox again after shutting down my computer (or even just closing Firefox and then opening it again) it just opens Google which I have set as the home page.
I have tried resetting the option and then restart in order for the changes to take effect but nothing happens.
It never opens up the tabs I had when I previously closed it.

And here is the most important problem:
2) The last couple of days, Firefox encounters a lot of problems, specifically on Youtube.
a) It doesnt show the thumbnails for many of the videos (either in the "Related Videos" or "Other videos from x user" menus or even the front page).
b) It takes a lot of time to load the comment-creation box when viewing a video.
c) When viewing a video directly from the channel of a user, for a minute or two I cant pause the video, adjust the volume or generally anything that is customised through the bar that is right under the video which shows the duration etc.
And it takes it a lot of time to load other things under the video such as the descritpion tab, the comments tab etc.

Note: My internet connection is pretty fast so I rule out that possibility, and besides the video itself loads normally. The rest of the page though is a mess.

Now within those last days there are two "changes" that I can link to the second problem. Recently Firefox 3.6 was released to which I upgraded. And also I had a Microsoft update almost right after that. Unfortunately I cant remember exactly when the problem appeared so I cant tell for sure.
I also have tried disabling and then enabling my add-ons one by one to see which one is the culprit but none of them were.

EDIT: I just tried visiting Youtube with Opera 10.10 and the same problem appears. Up in the address bar where it shows how many elements are loaded it tells me that only 21/24 are loaded. In effect it cant load the page fully.

 

I use CCleaner often and in fact I did scan my PC both with the File Cleaner and the Registry Cleaner CCleaner has just yesterday. The problem still exists.

And yep I have the latest flash player plugin installed.

 

Sorry to bump this but the youtube problem has fixed itself. I cant tell for sure how, but before it did my Vista encountered several errors while I was browsing some folders (something about run.dll or something like that, not sure).
I dont know if they can be connected but whatever.

Anyway if anyone can now help with problem No 1 I would be very happy.

Thanks.

 

Just checking but are you sure CCleaner is set to delete FF cache?

I didn't find anything definitive at mozillazine that addressed your problem. A work around would be tab saver addon it automatically saves tabs when you close FF and puts options to restore them in the Tools menu. (I rarely use it but I have never figured out how to get the FF Save and Quit dialog to show when I need it. Tab Saver solves the problem for me.

 

Well, yeah. In the second tab in the Cleaner option where it has the check-boxes for Firefox, all are checked except for the last 2.

Anyway I guess I'll try this add-on.
Thanks for the replies.