Heres my method in PSP5:
Get framegrab and resize to 2000 pixels wide
Create new layer. Call it outline
Pick a highly visible colour (I use lime green)
Using the bezier tool (same as straight line, just go from Normal to Bezier in the tool window) and a line width of between 2-4, trace the outline of the image on the new layer. Make sure anti-aliasing is OFF.
When you have the outline, fill the lines in black
Colour the image
Delete the original layer and Merge All (Flatten) the image
Resize to about 400 pixels wide, and all the lines should be smoothed for you.
Thats how I do it anyway
Don't forget to save regularly. And save a work-in-progress copy before flattening the image