I have the "won't download from Android Market" all the time... trick is, just download it from a browser instead. No need to reset the whole phone, especially since it's usually an intermittent problem!
I think there's a version of CyanogenMod for HTC Desire, might be worth looking into. I have it on my Samsung Galaxy Ace and it really opens up what you can do... SuperUser app allows root permissions, for example.
It is true, TiVo IR remotes are known for being slow to respond. I much prefer using the app or a USB keyboard to get things done quicker, especially since you can get the SD menus by pressing F11.