Please post your computers specs, see the posting system specs link in my sig. Don't forget the brand and model of the power supply.
Restoring to before you uninstalled NAV wouldn't make much sense, it's possible the other restore points got corrupt so let's try to repair your current installation instead of restoring to a previous restore point. Please try the following steps, stop once you're able to boot normally :
See if you still have norton related errors in the event viewer after running the removal tool : Symantec, SAVUI, SAVMAIN, SAVRT, EraserUtilRebootDrv.sys, SPBBCSvc are all related to Norton. If so then try another uninstaller. Ask one of your friend that has the same version of norton to go to the help => about tab in Norton to see what version it is.
If that didn't help then make sure you have an XP SP2 CD (if not then
create one). Then boot into safe mode, go to start => run and type sfc /scannow (mind the space after sfc). You'll be prompted for the XP SP2 CD if the system file checker detects corrupt system files and can't find a backup on the hard drive.
There was some message about a corrupted user profile, see if you can create a new admin account in safe mode (don't use the same name as the old one) then follow the instructions in this link :
How to recover the damaged user profile in Windows XP.
Once you've copied your old profile settings into the new one see if you can boot properly. Else unplug the ethernet cable, turn the router off or disable the wireless card in the device manager, boot in safe mode, go to start => run and type msconfig. Go to the startup tab and untick everything then go to the service tab, tick "hide all microsoft services" and untick all non-MS services. Restart (each time you make a change in msconfig you'll get a warning that you're in selective mode after restarting the computer, tick the box then click ok) and see how it goes. If all is fine then retick those items one or two at a time and try to pinpoint the one that's causing your troubles. Don't bother reticking items like qttask, adobe, reader_sl, office updater, ... you don't need those ones.
Chkdsk cleaned minor inconsistencies on the drive, I'd rerun chkdsk c: /F (this will run much faster than the /R test since it won't scan the whole drive for bad clusters) and see if it helps since last time it booted fine after that. If it finds errors again it means something creates errors in the file system. Check your temps and voltages in the BIOS (search for some hardware monitor or pc health status screen) and test your memory with memtest : download, unzip and burn
memtest86+'s bootable .iso image file using a burning software that can handle .iso files. Enter the BIOS at startup and set the boot priority to CD-rom first. Leave memtest run overnight and report if it finds any error.
If nothing helped try a repair installation. You'll have to
uninstall IE7 first if you had it installed. Then boot on the XP SP2 CD, press enter to setup windows now, accept the licence agreement, select your current installation and make sure the option you're given is to press 'R' to
repair the selected installation. Follow the instructions and see how it goes.
edit : ok, seems you jumped directly to the last step
You'll have to reinstall the latest critical updates from windows update. If you had IE7 see if it still works. Report here if there's still any problem.