svchost app error im totally stuck

I have looked through other posts on svchost app errors, and have gone through the advice given, but i am unable to download the fixes from windows, i can get online but when it comes to downloading or going on windows update it, it wont do it, the svc error is the instruction"0x7564d383 ref memory at 0x00000060" the memory could not be read, also it displays 0x7c910863 0xffffff8
I am a complete learner in computers, but am good at following instructions, lol, i would really appreciate any help to solve this problem, as my teenage son is hogging my laptop,
The operating system is windows xp

 

hi dom thanks for taking the time to read my problems,
to answer ur questions
the service pack is no 3 of xp home edition
the error appears as soon as u turn the pc on before u log on and everytime i click on an icon. the sound has also dissapeared.
i can get online but its temperemental, can get onto windows support site but when i tryto get on windows update, the web page can no be displayed, the same when i try windows update from the start menu
thanks fiona