Hi Troyan –
I usually use the NTSC D1 Widescreen Sqare Pixel preset. It’s under the Film/Video section in the presets in the render settings Output tab. Should be 864 x 486.
Of course Adobe has decided that that aspect is now different. Something like 872 x 486.
In Cinema use the preset…it should make it big enough to look good, but small enough to be manageable.
Hope that helps.
Tim