on native res: a 19" CRT typically has 18" viewable so a 19" viewable TFT at 1280x1024 will probably be of similar size to your 18" CRT screen at 1152x864? Tbh I prefer the 1680x1050 I get on my 20" widescreen TFT by a long way over anything smaller. Anything much less that 1024 vertical I find very restrictive.
wrt: lower refresh.
on a CRT the main reason you want a high refresh (imo) is to avoid screen flicker. Even in fast action games I find a fps of 30+ quite acceptable, and anything 50+ makes little difference to the experience for me. TFT do not suffer from flicker so do not require high refresh rates, and 60Hz easily allows for good fps in games.
Find a friend with an up to date TFT and have a go... can't beat experience!
p.s. you don#t have to use the native resolution, and some TFT do a fine job at less-than-native resolutions. Again you have to see it for yourself