How do I remove all children elements from a node and then apply them again with different color and size?

So I have the next force layout graph code for setting nodes, links and other elements:

var setLinks = function ()
{
    link = visualRoot.selectAll("line.link")
        .data(graphData.links)
        .enter().append("svg:line")
        .attr("class", "link")
        .style("stroke-width", function (d) { return nodeStrokeColorDefault; })
        .style("stroke", function (d) { return fill(d); })
        .attr("x1", function (d) { return d.source.x; })
        .attr("y1", function (d) { return d.source.y; })
        .attr("x2", function (d) { return d.target.x; })
        .attr("y2", function (d) { return d.target.y; });

    graphData.links.forEach(function (d)
    {
        linkedByIndex[d.source.index + "," + d.target.index] = 1;
    });
};


var setNodes = function ()
{
    node = visualRoot.selectAll(".node")
        .data(graphData.nodes)
        .enter().append("g")
        .attr("id", function (d) { return d.id; })
        .attr("title", function (d) { return d.name; })
        .attr("class", "node")
        .on("click", function (d, i) { loadAdditionalData(d.userID, this); })
        .call(force.drag)
        .on("mouseover", fadeNode(.1)).on("mouseout", fadeNode(1));
};

//append the visual element to the node
var appendVisualElementsToNodes = function ()
{
    node.append("circle")
        .attr("id", function (d) { return "circleid_" + d.id; })
        .attr("class", "circle")
        .attr("cx", function (d) { return 0; })
        .attr("cy", function (d) { return 0; })
        .attr("r", function (d) { return getNodeSize(d); })
        .style("fill", function (d) { return getNodeColor(d); })
        .style("stroke", function (d) { return nodeStrokeColorDefault; })
        .style("stroke-width", function (d) { return nodeStrokeWidthDefault; });

    //context menu:
    d3.selectAll(".circle").on("contextmenu", function (data, index)
    {
        d3.select('#my_custom_menu')
          .style('position', 'absolute')
          .style('left', d3.event.dx + "px")
          .style('top', d3.event.dy + "px")
          .style('display', 'block');

        d3.event.preventDefault();
    });
    //d3.select("svg").node().oncontextmenu = function(){return false;};

    node.append("image")
        .attr("class", "image")
        .attr("xlink:href", function (d) { return d.profile_image_url; })//"Images/twitterimage_2.png"
        .attr("x", -12)
        .attr("y", -12)
        .attr("width", 24)
        .attr("height", 24);

    node.append("svg:title")
        .text(function (d) { return d.name + "\n" + d.description; });
};

Now, the colors and size dependencies changed and I need to redraw the graph circles (+all appended elements) with different color and radius. Having problem with it.

I can do this:

visualRoot.selectAll(".circle").remove();

but I have all the images that I attached to '.circles' still there.

In any way, any help will be appreciated, let me know if the explanation is not clear enough, I will try to fix it.

P.S. what is the difference between graphData.nodes and d3.selectAll('.nodes')?

Your answer will work, but for posterity, these methods are more generic.

Remove all children from HTML:

d3.select("div.parent").html("");

Remove all children from SVG/HTML:

d3.select("g.parent").selectAll("*").remove();

The .html("") call works with my SVG, but it might be a side effect of using innerSVG.