The short answer is yes.

Linux has disk quotas for users and groups.
LIDS (Linux Intrusion Detections Service) allows you to restrict access to files (even to root)
Tripwire will monitor file changes and Snort for network scans, probes, or attacks

As far as faster or more stable, it depends on what you load on the system. Linux is easy to do a "lean" install therfore eliminating overhead that could be used bor something else.

Just a few answers for ya.