Difference Between IPhone 1 and IPhone 4?

I'm going to get my father a new Iphone for his birthday. He's been using the IPhone one for a while and its just time for an upgrade… I want to make sure that the controls of the IPhone4 are the same if not, extremely similar to the IPhone1. I don't want to be giving my dad an entirely new piece of technology that may look strange to him, causing him to run back to the IPhone1, otherwise that'll make the gift a total dud.So, how different/similar are these phones pertaining to controls (how to call, speak&search, internet, 4# pin lock, etc.)

Added (1). Edit: I'm going with the IPhone4 because its simply cheaper than the newest IPhone5 and not totally outdated. Surely either of them is better than the IPhone1.

By changing the 1 into a 4, they can trick people into paying even more.

The 4, has the PITA Siri as well, and a new camera. What do you mean 4#?

Not much, just trying to get you to spend more money.

Its all the same for the most part, just way WAY Way more powerful.

You're father will have absolutely no problem with adjusting to the iphone 4! Nearly everything is the same software wise, but everything the iphone 4 does do the same it will do it faster smoother and overall better than the first generation model.
I'm sure he will be more than happy with his birthday present.

Hardware wise, the CPU and RAM and Camera and screen and digitizer and Attena and radio are significantly better

Button wise, its the same

control/software wise… Very different… Your dad has a 1980 Honda Civic… And you want to buy him a 2011 Honda Civic… So, you tell me how different it will be? Sure, he can still drive it… Its just another stupid car… But the added features might make old conservative people go crazy.

Http://www.gsmarena.com/compare.php3?idPhone1=1827&idPhone2=3275

See for yourself & yes the 4 is definitely better than the 2G (original). They function the same, except that the 4 has more features of course as it runs the latest version of iOS & would gain even more when the iOS 7 update comes out next month.