SP2 Installer

I downloaded SP2. I went to install programs back on my
system that I had on before and I couldn't It said my
windows installer was not the correct version or that it
was corrupted. So I unistalled the update and restored
back to before the update and installed my programs
without any problems whatsoever. I'm not sure if anyone
has had this problem but it deffinately affected my
decision to keep it on my system. Some of the programs
that gave me the installer error was MICROSOFT office
2003 and Jasc Paintshop Pro 7. So I'm not sure what
happened but I certainly hope this is not another race
for software makers to keep up with a new version to
accomadate a new update.
Any feedback on this issue would greatly be appreciated.
Lynn