Hard drive partion behaving wierdly, how do I diagnose?

[Arthur Pemberton]

Hello,

A recent 'crash' of my FC3 took down FC with Mozilla running. My mozilla 
profile is symlinked to a vfat (fat32) partion. Since rebooting, this 
partioning starts of from boot as rw, but then some how, at soem point 
becomes ro, that causes some troublesome problems. I've already rsynced 
all the important folders I could recall to an NFS mount.

What I need to know is how do I go about diagnosing and hopefully fixing 
the problem. Preferable what tooks that come with the distro can I use 
for this purpose.

Thank you.