Is there a way to get rid of the white lines around the edges of the screen?

It's been years since I played the game, but I don't remember those borders existing on old computers. Is there anyway to remove them so that edges blend into the black edges of the monitor?

Also is there anway to force the game into original aspect ratio 4:3 (black side borders)?

I'm not sure about the white borders, but the 4:3 aspect ratio should happen regardless. If it doesn't, it's probably a setting on your display somewhere.

If you run it in windowed mode it'll definitely be the proper aspect ratio.