Samsung Galaxy Ace by far. It packs a 800 MHZ processer which is much faster than the Wildfire's 600 MHZ. It also has a higher screen resolution, at 320x480 as opposed to the Wildfire's 240X320 which makes it more optimised for more apps on the Android Market, and makes everything appear nicer on the screen. Speaking about the screen, the Galaxy Ace has a 3.5 inch screen while the Wildfire only has a 3.2 inch. If you are dead set on getting an HTC, the Wildfire S is coming out soon, and there are many HTC phones from 2010 whose price has decreased, but are still modern such as the HTC Desire.
