Here's my plan of action;

1. backup
2. try replacing explorer.exe in safe mode using a different file explorer to explorer.exe
3. it the above doesn't work I'll just re-install xp

the GRUB issue is ompletely unrelated to the problems I'm having with xp. Linux was installed on a different hdd to the one that xp is currently installed on. if i were to install an os onto that hdd and try and boot it would come up with the grub menu even if it had been formatted. its not a huge problem at the moment but it could be soon if i use it to boot from.