How can I get rid of hackers in Halo 1 PC?

As with most games, if the game's security is not up to the task of blocking unscrupulous players, the only option is to avoid playing on public servers and just play on private servers or with friends.

To elaborate on Macha's answer, the only way to rid the game of cheaters is to fix the game, and that's up to the game manufacturer. Considering that this particular game we're talking about was released in 2001, it's unlikely that Microsoft or Bungie would release one at this point.

You can actually kick/ban them if you are the Host.

http://hce.halomaps.org/index.cfm?nid=314

Commands:

• sv_ban [cheater]
• sv_ban_penalty 5m 1h 1d 1w [perma]
• sv_banlist
• sv_unban [innocent]