From research I have found that Thor or Tor in some versions is most likely Odin's eldest son. Thor's mother is Jord who is not Odin's wife.

alternative forms of a gene are called as alleles..

Woden was an alternative name for Odin the head god or all father

Thunor could possibly be an alternative form of the name Thor

No they are alternative versions of a gene.

Do you mean Don't Cry by Guns n Roses? There are two versions on Use Your Illusions, the original on I and the alternative on II. I don't know about live versions.