I've got a 28mm gatorskin on a ridga snyper rim (17.5mm).
So yes
This is the post you need to read.They should do. Ace19 rims are 17mm internal, so should take anything from 25-37mm tyres (and probably a bit bigger)
Rim details
Sheldon's bit on tyre sizes (scroll down to about 3/4 of the way down the page)
Alex Ace 19 is a 700c rim it seems, which is the same as 28" generally in this country (albeit there are some 28" rims that aren't the same size), and the same as 29 (don't ask why, but if you must know read this...).
37 I would expect is the width of the existing tyres in mm.
Tyres that fit will say something like 700xYYc on the side wall, where YY is the width in mm.
They should do. Ace19 rims are 17mm internal, so should take anything from 25-37mm tyres (and probably a bit bigger)
Rim details
Sheldon's bit on tyre sizes (scroll down to about 3/4 of the way down the page)
How do they feel? I've just got some snypers and I'm thinking of 28mm gatorskins or sport contacts for them instead of the 32mm marathons currently installed.