The icons pack would contain png icons. To use them, unzip to any location; then on your dock, right-click on each item and go to icon settings. In the dialog box, click on the '+' button (near the centre-left) and navigate to whatever folder you put the icons in. The folder should appear in the tree view of the dialog box, from there select it to view the icons and click on the one you want to use for the selected item and press ok....You'll have to select the icon for each item, there's no automatic installation.
The taskbar on top thing is a very very easy and newb question and there's also a thread on this. In the row of links above the thread title, there is one called Search. Click on that, type "taskbar on top" in the text field and press go. You'll be surprised at how much that tiny button can serve up,
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