Hanging ITUNES/MSN/TRILLIAN Streaming issue?

Ok long story but here goes \

Apologies if this is not in the right forum as I don’t know what the error is I am unsure where to put this.
please steer me to the correct one If I am wrong/

Son has new pc that a friend built for him.

I have run AIDA and I am not sure what you need but here are some of the specs


Computer
Operating system Microsoft Windows XP professional
OS Service Pack Service Pack 2
IE 6.0.2900.2180

Problem is what I think is a port or streaming issue

had issues with reading DVDs initially and installed K lite Codec pack which worked

However from the get go
Unable to access windows messenger – hangs
MSN downloaded – hangs
Google earth – hangs
Trillian – Hangs
ITUNES – can access media player etc but not the store – hangs
Can log on to some on line games ok

I have made sure XP firewall is off I have tried with out Zone alarm
No luck I have reinstalled IE no luck Have Firefox no luck
EMessenger – hangs though I did get through ONCE

Now the person that built the machine is two states away and does not access any of the messenger programs so was not tested before sending . Which is fine but having a teenager who cant access the programs sheshhhhhhh it is like his support system has been removed.
Can anyone save this mum and her sanity??
The PC has lots of programs loaded like paintshop etc so I don’t want to have to reformat as I don’t have the discs and um would not know how.