So, I guess my grandosn is out of luck trying to get YouTube videos to play on his Archos 32.
Sounds like a thankless attitude for the folks who have volunteered time for a solution for you. Yes, your device can play youtube beautifully. It is a very old design, so probably requires loading new apps for flashplayer or at least youtube.
I dont know where you are starting from in terms of software... adobe and youtube have just dropped bombshells by withdrawing flash player apps from the market and youtube changing format of their videos. Then google seemingly stopped providing new copies of these apps for this old device.
Didnt you notice someone kindly provided a direct ftp download of a working version of youtube? You need that and a version 10 or 11 flashplayer, which you may have. It is very doable, but followup questions should be in the general gen8 section since the issue is common to that whole family of devices. With such an old device, you wont find much of an audience left in this specific section.