Textual nonsense in the Qur'an

In a previous post, I suggested that one of the reasons why I cannot believe that the Qur'an is divinely inspired and that Muhammad was the prophet of God is that, despite claims to utter clarity made in the Revelation, there are many verses in the text that seem to defy any logical interpretation at all.  
For example, can any Muslim or scholar please explain the following verse to me? (I have given multiple translations lest I am accused of cherry-picking the most obtuse...)
YUSUFALI: If ye fear that ye shall not be able to deal justly with the orphans, Marry women of your choice, Two or three or four; but if ye fear that ye shall not be able to deal justly (with them), then only one, or (a captive) that your right hands possess, that will be more suitable, to prevent you from doing injustice. 
PICKTHAL: And if ye fear that ye will not deal fairly by the orphans, marry of the women, who seem good to you, two or three or four; and if ye fear that ye cannot do justice (to so many) then one (only) or (the captives) that your right hands possess. Thus it is more likely that ye will not do injustice. 
SHAKIR: And if you fear that you cannot act equitably towards orphans, then marry such women as seem good to you, two and three and four; but if you fear that you will not do justice (between them), then (marry) only one or what your right hands possess; this is more proper, that you may not deviate from the right course.

How does my decision to marry multiple wives (or one of my slave girls/captives) have anything whatsoever to do with my inability or otherwise to deal justly with orphans? (And that's before we start on the idea that God should find it acceptable that I should marry a captive...)

Am I missing something here? Am I being stupid? 

This is supposed to be God's final words of wisdom and advice to us? Our omnipotent, omniscient maker wanted this passed down generations; wanted this learned word-for-word in madrassas; thought this, when chanted by children who have no idea of the meaning, would help them get into Paradise?

And because I question and research, rather than blindly accepting what I'm told, and find that there is no logic to it all,  I'm going to be burned in Hell for eternity.