This should give you a general idea of what to set in the Game Configurations tab, there is a step by step list below the picture if you need help.

Open up Valve Hammer Editor, and goto Tools->Options.
Click on the Game Configurations tab.

Under Configuration:
Click on the Edit button, and you'll want to Add a new configuration, with the name of "Street Wars".

Under Game Data files:
Click on the Add button, and add the Street Wars FGD file, if you do not have it you can download it here.

Under Default PointEntity class, and Default SolidEntity class:
These do not really matter, they vary per person, but here are my choices ( see the picture ). Basically, these show up when you make an entity, they are defaults (hence the name), and they're not set in stone.

Under Game Executable Directory:
This is where ever you installed half-life. Mine so happens to be at "d:\games\half-life\".

Under Mod Directory and Game Directory:
These will be set to the same thing, I've set them according to my directory structure: "d:\games\half-life\streetwars".

Under RMF Directory:
When you goto File->Open, this is the directory that will show up by default, change it to where ever you save your maps.

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