Windows xp restarting constantly

what have you done recently on your pc? Any hard/software upgrade, give more details to narrow down the issue.

I think you should use Bootable disk to solve problem of your computer because if safe mode is not working then better way is to repair your OS and take backup.

What do you mean safe mode not working?
Does it restart again when safe mode is loading?



That IS safemode!
The "messages like directories" are the minimum devices, drivers, files (whatever you call them) that are loading (on slower PC's it takes a while) so that the PC can open , but it loads without facilities like cd rom, sounds, printers and other services, so you can see if with minimum things loaded you can do something, or in your case ,if you do get that error or not, and troubleshoot it!

Just let Safe mode load all those, and then finnaly open Windows.
Is Safe mode gets stuck somethimes, maybe it need a little more time to load whatever it is loading, or if it gets stuck, there are some files that you can cancel loading of.
When you look at bootom center it sometimes asks you if you want to cancel loading something, if it gets stuck on a file like that you can cancel it (the old Y or N key)

If you can, while at the F8 menu disable automatic restarting, or you can do that from safe mode by right clicking desktop, and go to properties go to advance tab and to Startup and recovery . Then uncheck automatic restart and click ok. This is necesarry to see your actual error message more then 1/2 a sec' so we could figure out what it is.