Problems Composing Posts

I have a small problem and a major problem since upgrading. I used WordPress Automatic Upgrade as I have for the past few upgrades> I am unaware of any problems associated with that.

The small problem is that when I go to compose a post, every drop-down on the edit page stays in the drop-down position. They will not change.

The major problem is that I cannot use any graphics in my post since upgrading to WordPress 3.0. I go through the process of selecting a graphic the same way as always. When I click on Insert into Post it immediately goes to a blank browser page with the word Done in the bottom, left-hand corner. It goes no further. It does not return to the edit page and no graphic is inserted.

It is unlikely to be significant but before the upgrade the graphics pages were centered. Now they are completely to the left of a wide-screen monitor. These are the only changes I have noted so far that relate to composing a post. Because of these problems I have not attempted to actually post, so there could be further problems.

I use, and have for a long time, the following plugins related to editing:
WP SuperEdit
TinyMCE Advanced