Hanging Problem when rendering or encoding

[prospero]

Ladies and Gentlemen
I have been having a recurrent problem with my system (See details below).
Whenever I am rendering a movie using ULead VideoStudio 8 or Windows Movie Maker it hangs such that I can't even CTRL+ALT+DEL and have to turn off the machine.As this tends to happen only on large files I have worked around it until now;however I have recently started using TMPGEnc to encode Divx and that also hangs.
I can only assume that it is some kind of conflict with other processes working the the background as my system, although not up to the standard of some on this forum, seems good enough for this work (At least I think so!!).
If someone could point me in the right direction I would be very grateful
Best Regards
Chris
System Specs:
Asrock K7VT2 2.00 Mobo
1gB Crucial Ram
Athlon 2.0GHz XP
HDD 120 and 40 Gb
XPhome SP2
Hercules 3D Prophet 9200/9200SE Series
LITE-ON DVDRW LDW-851S

[Strider]

Turn off unnecessary processes might help you problem and to get help in turning off unnessary processes this website should help you : http://www.blackviper.com/

Also make sure you hard drives aren't too defragmented which will slow you rendering down considerably.

[prospero]

Ladies and Gentlemen
I am re posting to this thread as the problem is still occurring.
The freeze seems to have no logic to it as I have stopped every process that I possibly can and it still occurs. I have tried TMPGenc and Ulead Video Studio V8.0 and Nero 6 and it still occurrs.
The support for these apps just suggests uninstall and re-install which of course I have done, I have also de fragged and uninstalled any apps that I don't use.
Short of re formatting and re-installing slowly I am at a loss. The only thing I can think of is maybe there is a write to disk error, can anybody suggest a way in which I could narrow this down???
Best Regards
Frustrated Englishman in sunny Belgium listening to classic rock from San Francisco... Isn't the internet great
System specs
As above