stupid question

[Eugene Vinokurov]

'chmod -R o+w /' had been done on filesystem
reinstall is impossible 
chmod -R o-w / , chmod o-w /, and chmod o+w /tmp /var/tmp seem to help
What problems I have to expect ?
Is there any way to restore default permissions for system directories?
Maybe I have to check something?
Please, help

services working: sendmail, apache, mysql, proftp

p.s. sorry for my poor English