REMOVE HUD
The HUD (the yellow text at the bottom of the screen that displays your health, armor, time, and ammo) is not removable by console commands. There are two ways of hiding it, one is physically hiding it by using widescreen (refer to the 'Widescreen in Vegas' tutorial) and the other is by use of invisible sprites. By using invisible sprites, everything will be gone from the screen except for the crosshair and the kills in the upper right hand corner. (Note: These sprites are from MovieMakers.nu and therefore I give full credit of this tutorial to them)
1. Download this .zip Moviemakers_Present_CS_Moviemaking_Cfg.zip
2. Put the 'Sprites' folder included in that .zip in C:/Program Files/Steam/SteamApps/Counter-Strike/cstrike
Tip: if you alread have a 'Sprites' folder, rename the original one to 'Sprites1' and put in the folder from the .zip. To change it back to normal, rename the 'Sprites' folder to 'Sprites2' and the if there was an original 'Sprites' folder, rename that back to 'Sprites'
3. You may use the MovieMakers.cfg file included in that .zip but I personally like to use cl_dynamiccrosshair "1" and a few other commands differently from that .cfg, refer to the 'Cleaning the Screen' tutorial
4. Once you have the sprites folder installed, and you type in all the cleaning commands in console, you're ready to go