Bulk updates and category tree

[CrystalPhoenix18]

A lot of products were uploaded to the wrong category - is there any way to export all the products in a specific category, make the changes, and re-upload the corrected products?  There are a few hundred, and changing each one manually through the back office is taking way too long.

Along the same line, the category tree in the product page in the back office is very narrow, and I have to reduce the screen to 50% to see the whole tree in order to re-assign categories.  Any way to change this?  In PS 1.6 the category tree was in a separate tab and was much easier to access.