Newest Version of FF 2 Locks Up Mac

I was have been running FF 2 for sometime on mi iMac OS 10.5.8 with CS3 . I wanted to download some new filters and got a message that I must update 1st. I did tis. FF was somewhat unstable afterwards (I am not sure if I successfully downloaded the new filters) and now locks up shortly after starting with runtime error "xfwi exception application encountered unrecoverable critical error and will be terminated". The same problem occurs with the standalone FF. I deleted my FF2 application folder and reinstalled, with the same lockups occurring. FF1 is also on my machine and runs fine (although it can no longer download filters since 2.0 came out).
I would like to stick with FF but cannot unless I get FF2 working again. I cannot tell if this is a version update bug or corruption of the filters.
What should I do ?

Thanks ! It appears others on this forum have had a similar problem.

To be sure I am deleting the right files, what form do the filter files take ?
for example, are they " Library_208_2.ffxml " ?
If that is the case, is your suggestion to move all these to the trash bin because they are corrupted and then download the filters I want once again ?

~ in a pathname means "home of current user", so ~/Library means <your user catalogue>/Library so the instructions are correct.