I've been wondering that for a while. But when I couldn't figure it out I'd just go to photoshop.

I've checked with a few people I know who use PSE1 routinely and they say NO to changing the color of the drop shadow. It looks like making a new layer may be the only way. I don't know if PSE2 is different.

So I experimented a bit with it and here's what I did (ELEMENTS 1).

Made a new document 7x7 white
Made a new document 4x4 blue (shadow)
Made a new document 4x4 red

red 4x4: Select>Edit>copy
white 7x7: Edit>Paste

blue 4x4: Marquee, feather 50 pixels, using the marquee clicked and dragged from corner to corner - got the marching ants
Select>All, Edit>Copy

white 7x7: Edit>Paste

dragged the blue layer under the red layer

blue 4x4: using the Move tool, selected the blue layer and positioned the shadow where I wanted it
Filter>Blur>Gaussian Blur - when this window came up I moved the slider for the radius I wanted.

It worked OK but isn't near as nice as the shadow from the Layer Styles menu. I have not tried it with an irregular shape. Since in Elements the Shadow off the Layer Styles becomes part of the image as opposed to a separate layer I doubt if there is a way to change the shadow color. I tried in Variations but had no effect.

When I used the blue 4x4 as the shadow Variations worked as far as changing color.

The other option was to select the blue/shadow layer and go to Enhance>Color>Hue/Saturation. When this window opens put a check in the COLORIZED box (lower right hand side) and move the sliders until you get the color you want. In any event to soften the shadow it worked best, for me, to select the shadow blue 4x4, using the marquee and specify the feather distance and after that is put into the layers in the working image to further blur using gaussian blur.