My personal opinion is:
1. Christians go directly to heaven.
Joh 3:13 And no man hath ascended up to heaven, but he that came down from heaven, even the Son of man which is in heaven.
Joh 13:33 Little children, yet a little while I am with you. Ye shall seek me: and as I said unto the Jews, Whither I go, ye cannot come; so now I say to you.
Mat 5:5 Blessed are the meek: for they shall inherit the earth.
Rev 5:10 And hast made us unto our God kings and priests: and we shall reign on the earth.
No one goes to heaven, Christ returns to the earth and after the Millennium and GWTJ, the Father comes to earth.
2. Non-christians are sleeping, waiting for the judgement. Not sure whether this "sleeping" means no conscience at all, maybe there is some like in a dream. Not a pleasant dream.
Not just non-Christians, ALL...
Joh 5:28 Marvel not at this: for the hour is coming, in the which all that are in the graves shall hear his voice,
Dan 12:2 And many of them that sleep in the dust of the earth shall awake, some to everlasting life, and some to shame and everlasting contempt.
1Th 4:15 For this we say unto you by the word of the Lord, that we which are alive and remain unto the coming of the Lord shall not prevent them which are asleep.
1Th 4:16 For the Lord himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God: and the dead in Christ shall rise first:
1Th 4:17 Then we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air: and so shall we ever be with the Lord.
Note the time frame? The dead in Christ rise AT HIS COMING. As for all who are dead now...
Ecc 9:5 For the living know that they shall die: but the dead know not any thing, neither have they any more a reward; for the memory of them is forgotten.
Ecc 9:10 Whatsoever thy hand findeth to do, do it with thy might; for there is no work, nor device, nor knowledge, nor wisdom, in the grave, whither thou goest.
All are unconscious until the resurrection(s), there are three.
3. Animals are sinless, therefore they have some special treatment after death. I am not sure of what kind.
The Bible doesn't say much about this but let's see if we can find anything that indicates animal/spirit life...
2Ki 6:16 And he answered, Fear not: for they that be with us are more than they that be with them.
2Ki 6:17 And Elisha prayed, and said, LORD, I pray thee, open his eyes, that he may see. And the LORD opened the eyes of the young man; and he saw: and, behold, the mountain was full of
horses and chariots of fire round about Elisha.
Rev 19:11 And I saw heaven opened, and behold a white
horse; and he that sat upon him was called Faithful and True, and in righteousness he doth judge and make war.
These are just a very few scriptures concerning these three subjects, I would recommend that you use a concordance and study these subjects yourself.