I'll try another one

Also, with regard to linking vs. uploading -- I MUCH PREFER LINKING, as uploading takes up server resources and bandwidth, and will eventually be a problem as we grow in size.

Eric,

I assume, for these reasons, that after a certain time period all old posts or attachments are deleted thereby minimising effect on server?

Nope. The files stick around forever, until I decide to delete them. It's ok, though. We're only using 171 MB of storage, so far, including everything on the site.