Anyways, onto the HOWTO. Once upon a time, I used Konqueror as both a browser and a file manager. It did both well, except I wasn't pleased with how it looked, and I wanted one set of bookmarks for the web, and one for my hard drive and not both at the same time. I also wanted one set of buttons for web browsing, and one for file browsing. How to resolve the dilemma?
Ok, open up konqueror in file browsing mode: on kubuntu the easiest way to do this is to go to the systems menu applet (on a default kubuntu install, it's on the bottom panel next to the kmenu button) and open up, say, your home directory.
Now, under the view menu in konqueror, select "Show Navigation Panel". This can also be done by hitting the F9 button on your keyboard. A panel should appear on the left side of konqueror. From the choices on it, open the metabar.
The metabar basically provides you with information on each file you select: size, permissions, previews. It also comes with actions and links. Those last two are how you're going to customize konqueror.
Right-click anywhere in the metabar area and select "configure metabar". Under the "Actions" tab that opens, add any file-browsing specific actions you'd like (things like "open in terminal" or the "up" button.) Then, under the "Links" tab, and any file-browsing specific links you'd like, things like your home directory or network places. When you've got the configuration you'd like, go to the "Settings" menu and select "Save View Profile File Management" and save your configuration.
I personally find other options of the navigation panel to be useless and it's presence ugly, so I hide it by default. To do this, open a terminal and type:
kwrite ~/.kde/share/config/konqsidebartng.rcand set the HideTabs value to equal true. Now when you open konqueror, only the metabar will be showing.
Finally, configure the main konqueror toolbar to include whatever buttons you like by right-clicking it and selecting "configure toolbar". I personally only keep web-specific buttons there, like back, forward, reload, home, etc. but customize it however you wish. Finally, consider adding some flair to your metabar by going to kde-look and searching for metabar themes. I personally like the Advance Blue theme from this set. To install them, simply download the file from the site, right-click the metabar, choose "configure metabar" and then under the "General" tab, press "install new theme" and select the file you downloaded. It will now be available as a theme option in the drop-down list next to the install button.