I think others may be able to help you but may need a slightly clearer description of the problem. Could you make one post for each question?
Sasi, Here is an example:
http://vimeo.com/112125072 (turn on the HD mode)
For the Helix body itself, you can create it with a Sweep twisting the profile along its axis
Notice you need 2 steps inside the command.
After that, just pattern along the proper curve (in that case, the curve is the tube axis.
In case you have ST7, as you have a complex shape, one way to flatten this is using the new Blank Body command.
But, yeah, as Frank mentions, would be interesting you give more details about what you want.
And here is another approach to build the Helix body, with a different way to get the flatten, also accepted in ST6 and, if I am not wrong, ST5 too.