Laying out a few nodes

I have a graph which is very strongly linked, which means looking at its nodes can be visibly confusing, and impossible to understand anything.

I'm looking for a way to make it easier to look at a few nodes which were selected by the user.
I tried to apply Force Layout on a only a group of nodes using AddNodesAndLinksFromCollection and giving it the Selection collection.
It wasn't good enough because the links that are from or to nodes outside the group, and links that visibly go through the group are in the way like white noise.
Is there a way for the layout to move nodes that have links going through a specified area?
Any other suggestions for making the cluttered graph seem more friendly?

Does your data have any logical grouping? If so, then maybe subgraphs can help.

You could increase the transparency of the nodes/links that aren't in the layout collection, to make them visually "recede".
you can google visualization of large graphs. 235,000 hits, including many Phd disserations, I'm sure. You might get some ideas from that.

Do you have a screenshot to show what you mean?

Maybe you want to change the default GoLink.Pen to be Pens.LightGray, and change links that have both nodes selected to be Pens.Black. The WebWalker sample exhibits this, but does not change any pens based on selection.