For a line you basically need a non-square aspect spell token... ie at 50 pixels per 5 foot square, a 500x50 pixel texture would be 10x1 squares or a line..
If you are want an variable size line, then no... Id suggest setting up a segment and have the player drag out more than one spell token..ie make a 100x50 pixel for a 2x1 line segment that you place down multiple lines to make the longer line/curve etc..
The other shapes are to do with different systems... some need 90 degree cones, and some use 60 degree cones... and then you have options to have the centre of the texture as the centre of the cone. Normally the cone shapes take up the full spell token and then rotation happens in the 'middle' of the spell token cone... ( The other shape just allow it to rotate on the cone focus point, but you have to track the cone with the mouse as it rotates to make sure you stay over the spell token etc.. but requires the bottom half to the spell token to be blank to allow the cone start point to be in the middle of the texture/spell token.)
Hope this helps,
Pete
edit: triangle has a 'flat' end to it, cone has a 'cured' end to it. Its again a difference between different rule systems.