Having a value of 0 or 1 shouldn't make much of a difference. It will both make the game run at maximum speed. How fast depends on the pc itself of course. Having doWaitVBlank set to false means that the game will not wait for the monitor's refreshrate, resulting in a higher framerates. This does however come with a price in the form of tearing. This can usually be seen with scrolling.

DelphiX' timer isn't framerate independent (afaik anyway). If you want this, you should look into timebased movement rather than framebased.
There have been questions about this in the past. A quick search should help.

There's a article over at gamedev that should be helpful
http://www.gamedev.net/reference/art...rticle1604.asp