I am planning to paint my wood paneling and want a smooth lineless finish.

I understand that I should spackle or caulk the grooves but some people say that the spackle shrinks and the grooves still show. Should I use wallpaper liner or textured wallpaper if I want to make the grooves disappear before painting? Or does it just depend on the type and quality and number of applications of spackle? What about some type of tape over the grooves?

Help!

With all the spackling or groove filling you may want to sheetrock over the paneling.

If not spackle will work. Just use mesh tape where one wall panel meets another. This is where the cracking usually occurs due to natural movement of the panels.