Msn Messenger 6 causes computer freeze

This problem has been causing me pain for weeks, msn
messenger 6 installs fine, runs in the background fine,
when i go to maximise a conversation window, or open a
new conversation window or sometimes a minute or 2 after
i have opened the window my computer completely freezes i
cant use ctrl alt delete or shut down or anything all i
can do is reset my computer and have to go through
scandisk etc. I formatted my hard drive and installed msn
messenger 6 and windows xp professional only and it still
freezes, my computer is a pentium II 300 MHz with 192 Mb
RAM 20GB harddrive NTFS file system (msn messenger
freezes when file system was fat 32 as well) and i have
all the updates including service pack 1 and interent
explorer 6 service pack 1, the version of msn messenger 6
i have is 6.0.602 which is the final release, graphics
card ATI 32 Rage LT Pro with signed windows xp driver,
directx 9b. I have done work as a computer technician and
i cant work it out, any help at all from anyone or help
from Johnathon Kay would be very much appreciated