Cannot open .pkg files in OS X 10.4.11 or run installer

I recently had to repair disk permissions & verify disk in Disk utility from installer disk. After I did this the only issue I have is opening a .pkg file or running installer. The installer window flashes and closes and does not run. I have right clicked to choose to "open with" installer and same thing happens. I have tried to locate installer from some of the other thread postings to open manually but same thing happens, nothing. This is not an isolated .pkg file, at first I was under the assumption that it was a corrupt file download but it is every file .pkg that I attempt. Any help? Thanks.