I cannot logging into windows the welcome screen freeze and that problem start after I changed regedit permission and tried to restore it throw pebuild bootable software and it says cannot import c:\..... not all data was successfully written to the registry some keys are open by the system or other proccess ,I tried also to reset the registry throw reset.cmd solution it doesn't make any different , then I use the recovery console to copy a new config files (system ,Sam ,security , default ) doesn't make any different and finally I tried to make repair throw windows installation cd after copying the setup files and I make restart to continue installation it start pop-ups error the file doesn't have a program associated with it for performing this action .Create an association in the folder options control panel and if its important to notice u I tried bootcfg command... any idea how to fix these error... :))))))))

Looks to me like you have well and truly broked it.

Best course of action now, grab a linux Live CD, boot to it and back up all data you need.
After that a complete rebuild, with format, would be in order.

I hope you have realised that the registry is not to be messed about with as it causes untold issues if you get it wrong.

What you need to do is use a windows xp professional disk get to the recovery console where you have the command prompt and type in ( chkdsk ) without the paraphrases if that comes back clean the type in ( fixmbr )

99% of the time that will fix it

If that doesn't work there are certain but rare windows xp pro disks that when you go to install them they will copy over all of your system files, please repost if this works