If want to uninstall Warlords make sure you do it before installing BtS.
When you install BtS it checks to see if Warlords is present, if it is then BtS doesn't install any of the Warlords content (music, movies, leaderheads etc.). If you uninstall Warlords afterwards, it removes all of the Warlords content which messes up BtS. Which means you have to reinstall BtS again.
Since you need the main Warlords files regardless, uninstalling Warlords results in just removing the scenario files which are pretty small compared to the main game data. So you shouldn't really bother unless you are pressed for space.