Just installed WP, can’t attach pics to posts

I’ve installed, and re-installed WP 2.5.1 and can’t attach pics to my posts. I could for a while … but now I can’t. I hit the ‘add image’ button, follow all the prompts, but when I hit ‘insert image in post’ button the screen goes blank (white) and sometimes I’ll see a ‘done with errors on the very bottom ofthe page.

What am I doing wrong? Is anyone else having this problem?

I installed WP via bluehost’s cPanel/simple scripts and Fantastico … would I have better luck with a manual install?