get the touch HD, it's absolutely WIN!
if you know how to use a computer then you shouldn't have a problem with the touch HD. Lots of cool applications out for it, that are free. Plus the screen is much better than the iphone (colour wise and clarity).
Plus if you tell orange you are thinking of leaving and getting an iphone (like I did), they should offer you a deal like mine
1200 minutes to mobiles
3000 minute to landlines
500 texts
unlimited 3G browsing
£24 per month incl VAT.
and the touch HD was just £28. (comes with 8gb micro sd card).
Im on my third WM phone (HTC Touch) and had been looking at the Touch HD but I am being swayed towards an Iphone because of the simplicity.
Ive done tweaking on all my phones and spend too much time on XDA Developers site but to be honest I need a smartphone but have got bored of Windows Mobile.
I will wait and see if a new Iphone comes out and how WM6.5 looks before deciding.