ORAC's right - the res of the 19" CRT is better, for games that's the key.
The LCD's from DELL are both good, remember that the 17" LCD is close to the screen size of a 19" CRT. The 19"LCD has a pixel pitch that is more than you really want - 0.27 is OK less is better.
The deciders for me are - radiation exposure (hours in front of a CRT are not as good as hours in front of an LCD!) - power consumption (LCD's usually win hands down) - and finally real estate (LCD's win again).