1. according to this http://www-03.ibm.com/servers/eserve...s/redchat.html
it supports Redhat v3, 4, 5 so Fedora is worth a try. However, if this is a serious (ie business or equiv) use system, I'd suggest RedHat or Centos (Redhat without RH logos/support), as the turnover in Fedora versions is too high (13 mths iirc).
Also, Fedora is a bit bleeding edge, not recommended for serious work.
2. fileserving: Samba or NFS, your choice...