List all posts of specific categories?

When the Codex is back up (…), see this page on category templates:

http://codex.wordpress.org/Category_Templates

In summary, you could create a category.php for your active theme (if one doesn’t already exist), and in this edit down The Loop to display just the title of each post.

Then to display *all* posts in a category (while retaining whatever your posts-per-page setting is elsewhere), I’d suggest this plugin:

http://mattread.com/projects/wp-plugins/custom-query-string-plugin/