although i don't have any log (for now) i'm writing here because i've seen a similar situation in this topic http://www.bleepingcomputer.com/forums/topic292567.html
and there were many experts that helped this person to solve his problem. I see that he was able to produce logs with a boot cd (OTL) to figure out what caused the non-boot.
It all started with a fake antivirus installed when i was visiting some (safe, i thought) internet pages, without my permission. Avira Antivir was closed down and there were messages from the fake antivirus (you are infected, scan now,ecc...). i ran malwarebytes or superantispyware, can-t remember and they cannot solve the situation, so eventually decided to use Combofix. Now blame me for my silliness, i had used it in the past, when suggested, and never had a problem.
Then the pc rebooted and windows said that the file isapnp.sys was missing or corrupted. I extracted it from xp cd and put it in the drivers folder. Problem solved, i thought. No, now after the bootmanager (in the past i had set it to last for 3 seconds so in case i have problems i have time to press f8) there's cpu activity for 2 seconds and then the screen remains black. No loading bar. nothing is loaded any more.
Tried to reboot, and run safe mode. it only loads some files and lines appear and then stuck again, no cpu activity. I've tried to leave it overnight but never booted windows. If i use a linux boot cd or any boot cd i'm able to access my partition, my files, everything seems ok. Combofix has created no log (think it didn't finish it's work), unfortunately, however there is a C:/combofix folder with many files, if this can help.
Things i've tried also using XP cd: fixmbr, fixboot, bootcfg /rebuild. repaired xp installation 2 times. last good configuration, chkdsk /p /r
i've also tried to plug my hd on an old pc and see what happens... guess.... stuck always at a black screen also in safe mode. same symptoms, so i imagine it's not hardware related.
I hope to find one of the team that can follow me, as i would not like to format (or switch to linux :D ) , i want to try everything before giving up.
i'll really appreciate your help