Several of my CS2 Filters have disappeared

Question

Not sure what's happened, but 8 tools under "filters: have suddenly disappeared. By that, I mean the names are visible, but dimmed.) Although I use them all at pretty frequently, the one that I need most for a current project is the "Render" tool, but two of its four options are missing.
I have already tried returning to the default settings, both by using Control/Option/Shift and by removing the Adobe CS2 Settings Folder from the Library,  but  in  both cases, after restarting Photoshop  only the last used  filter tools are available (not the full list of  original default ones).
Have ready every  Help file I can find on Google, but so far have had no success. Any further suggestions would be much appreciated.

Answer 1

Thanks to you both for your input. For the record, when mentioning my earlier attempts to correct the problem, I forgot to mention that I also had tried  the  Command/Option/Shift combination, but  it had not worked either.
Also checked and found that the application and folders were already in the proper locations.
But I think you found the source of the problem, Tao Lao. I played around with those document settings and found that the Filter options were all restored when I created a new document; just not in the  newly  created  files. But I also was able to gain full use of the filters by changing the mode and  bits per channel of the  documents.
Which leads to a new (related) question:
The goal of  my project has been to copy 100-150  childhood photos of our older son, which I intend to transfer to a CD for him. In order to organize them in a way that makes it easier to locate  specific photos, I've been creating small collages, consisting of 4-6  photos per page. While most are  colored photos, some of the older ones are black and white. In some cases,  I've also  replaced  distracting  backgrounds with new  ones, using the Cloud Filter.
My guess is that was part of the underlying problem I ran into yesterday. but I think I found a work-around. I discovered that by creating the backgrounds as separate files, I'm able to import them  and incorporate them into the collages where needed; then save the documents as RJB Color files  with 16 bits/channel.
My new question is: Now that I've out all this effort into the project, do you think that as long as I continue to save the  files in the above format my son will be able to access the files on his PC/Windows  computer, even though they've been created on a Mac? 
My first thought was to merge all the photos on each individual collage (both for convenience and to save disk space), but on second thought  I'm now also  considering  saving them as layered  files, so he can access individual photos if he wants to.
Any thoughts on  those options?
Again, thanks for  your earlier recommendations.   They not only appear to have solved a problem, but I learned something new, as well.