Yum updated php/mysql & WordPress has lost all my plugin options? Related?

I have got a nightmare presently, becuase although my blog is still working and I can add articles to it..there seems to be a huge amount of plugins and options gone missing from the ‘options’ menu heading.

I run a Centos 4.XX server and basically I compiled a few RPMs of the latest apache, php and mysql (fully tested in the wild and working 100% on lots of other servers)

Anyway, I came to update my sitemap using the manual method in the admin panel…and ….ALL MY OPTION menus are gone except for the All in One SEO Plugin Options ???

I have tried upgrading to the latest version but even after lots of messing about I can only get a blank page on the upgrade URL….
presumably becuase all of my old plugins are installed?!

please,can anyone suggest what I should do to get my admin options back? or how I can upgrade successfully and retain my content?
thanks