"Jomar" asked me to reply to these questions of his, and I'm more than happy to oblige.
I don't know if my responses will be what he is looking for, but I'm answering them as frankly and openly as I am able to:

1. Why are you resting Doctor Who for a YEAR?!
To allow actor David Tennant the opportunity to pursue his stage career with the Royal Shakespeare Company....and, don't worry, it's not really resting it for a whole year, as there will be not only a Christmas special (already filmed), but in January of 2009, filming will resume for three film-length TV specials, to be shown late in 2009.
2. If Davies is handing in the hat, so to speak, why are accounts saying that the next 4 specials in 2009 will be between Stephen Moffatt and Davies? All that while Davies is saying "I'm done".
Possibly because they were already written by RTD. I believe that RTD may have penned the 2008 Christmas special. Often scripts for TV series are written as much as three or four months to a whole year in advance--which is common sense, as actors have to be hired, props made, locations found, etc.
3. Have we finally seen the doctor's 11th regeneration and hence the next-to last
one? Does this mean it's Donna/Doctor 2 that's the result of this?
There's a lot of debate about that. The Doctor did not fully regenerate. But, he did use regenerating energy. However, I'm sure that a good script writer could find a loop hole in this whole regeneration thing. The Doctor 2 and Donna weren't technically full regenerations, either.
4. It's expected that Davros has escaped again, what's new this time?
Nothing. Doctor Who without the possibility of Davros coming back, would be very dull indeed.
5. What happens to the maybe insane, maybe deceptive Dalek Kahn? Does this mean we have another ally to the doctor in the future?
It is unknown at this time, whether Dalek Kahn (or Caan) was destroyed in the explosion or not. I don't see "him" as an ally of the Doctor, but that's purely in any future producer's hands now.
6. How come the backfire only affected the daleks but not the entire Crucible?
Because, (and I'm not sure I'm entirely right, just my thoughts on this) I THINK it's because Davros specifically made these Daleks out of his own body, and the backfire was connected to their DNA, which the crucible is not made of, only the Daleks--which is why it didn't kill Dalek Kahn, because Davros didn't make him...though why it didn't kill Davros...?
7. After Rose kisses Doctor 2, realizing that that's the doctor she wants, why does she chase after the doctor when he disappears? Does she want to have afternoon tea with them before they leave?
Again, my take on this is that she knows Doc 2 ISN'T the same Doctor she fell in love with.
To use an anaolgy as a life-long pet owner: It's a bit like having to give up a pet you dearly love, for an identical pet from the same litter....it may look and act the same...but it's not the one that you knew first, and grew to love.
8. Does this mean the Mickey and Martha Jones will now be the new members of Torchwood?
Possibly. Again, it's up to the producers.
9. Why is losing all memories of the doctor called "death of one of the children of time?"
Losing your memory is a bit like death, isn't it? You lose a big part of who you are as a human being. Donna lost a huge chunk of herself--her very life, when the Doctor took her memories away
10. Wasn't Jack given the funniest line in "I cannot tell you what I'm thinking about now?".
Erm--I din't do more than smirk, I'm afraid. But then, I'm not as big a fan of that character as some people are (like the character, honest, I'm just not over the moon with him)
11. How does Martha know how to speak German all of a sudden?
She may already have known how to speak German. She may have either learned in in school, or while journeying across the world during that whole end of the world thing with the Master, Or--my personal theroy, she may have been required to take a course in German by U.N.I.T.
12. In the Torchwood base, where did that Time lock concept come from? I've heard of it in the Time Wars but how come Tosh could come up with it? Was there any revealed time studies by Tosh before? Why did it trigger? Because of the Daleks? Why? Was it because of Evelyn Myles loud scream?
I have no idea. I have seen some episodes of Torchwood, but probably Davies threw it in there, just because he wanted to mention it, or as a plot device, and not for any specific reason. After all, it IS a television programme, and not everything has to have a specific reason or function...sometimes a script writer can slip stuff into the script ("I was a father once") just as something to keep the fans busy chatting about.
13. How can Donna ever ignore the existence of the aliens, the Doctor in the future when it's going to be coming at her when she lives in this "new life" she has in the form of media and friends. Was it sufficient for her mother and grandfather NOT to confirm anything?
Maybe you didn't notice? But, the "old" Donna was a bit...shallow. Even in that last episode, she wasn't taking the Dalek invasion and planets moving seriously, but was on her mobile, so busy talking about one of her friend's weight loss, that she barely even noticed the Doctor saying goodbye to her.
But...I have a theory...okay, it's probably not going to ever happen, but I'm sooo-sorry to see Ms. Tate (one of the best companions EVER) to leave, that here's what my immagination would WISH to happen:
Donna--as a part Time Lord, knew what was happening to her, and figured out a way to come back later...retain her memories...if not the Doctor's mind, and find the Doctor again....because Doc 2 said that not all the threads were pulled together yet.
Oh, just wishful thinking...but that's what this show is sometimes all about.
OKAY, NEXT:
14. Why didn't the doctor invite Donna Noble's grampa into the Tardis? Not pretty enough? No men allowed? How about mickey?
Age, my dear. I take it you're young? I'm only 47 and I can't run any longer. Put simply, I'm sure both men might know that it would simply be too dangerous for Donna's grandfather to travel in the Tardis.
15. When did the doctor have the power to erase memories? What did he use to do this?
He's always had that power. He did it in the old series--I forget which episode now. The Doctor doesn't like it, but he can see into human's minds, he can plant suggestions in their minds, he can make them forget--well, it's basically like super-powerful hypnosis. It was part of the old series---the 4th Doctor saved Sarah Jane from the decompression chamber by using mind-power.
16. If donna cannot regenerate, how come we see a sort of regeneration after she got hit by the Dalek? Does this mean she can regenerate ONCE only?
But, Donna DIDN'T regenerate. What she got was a boost from the Doctor's regenerative ENERGY. She didn't physically regenerate.
CLAIRIFICATION: Davros' ray that hit Donna, didn't really trigger a regeneration...what it did, was that it zapped Donna's new Time Lord brain into existence.
