Easy Login Tracking Tool?

I administer 4 remote offices with 250 WIN95/98/ME OS PC’s for MI Talent Bank Registrations via Browser. I need a way to track each user at each station during the day to track Use Policy violations or damage since some are self service w/out supervision. They link via frame Relay T1 over proxy. I need to force each user’s time to be tracked and simply their name and last 4 digits of SS#. I can’t trust on-site staff to manually sign them iin/out and I need a tool that’ll require basic sign in/out to be tracked on each system. Trying to prevent sabotage or virus planting/hacking…HELP!
Pending upgrading our Proxy and getting Checkpoint is there a freeware or shareware product?