Further questions about wallets

[cryptotrade]

Thank you. You have been most welcoming and helpful with my questions so far. 

I have some further questions about wallets and I hope you can help me:

re: wallet.dat

I understand that I need to run appdata, but I don't quite understand what kind of file this is?

If I go into Windows 7 and search wallet.dat - there is no such file that comes up in the search.
Is wallet.dat not a file?  Is it considered an executable or a program of some sort?

Where EXACTLY does wallet.dat reside in the file hierarchy if I can't search it and can't see it?
Is it not on the C drive? 

If I can't search it or see it, how can I save it or rename it?

(Forgive my ignorance but the bulk of my training is more hardware based and not programming based, more WAN than LAN.)

Also - suppose I copy my wallet onto a flash drive and I put it in a safe place for a few weeks.
Now I go to use my wallet for a transaction.

Am I stuck now for hours while this wallet updates all the blocks to synch up?
I probably am, right?

And if you put your wallet away for a long time or "buried it in a back yard", then if you went to
use it in 2014 or 2015, wouldn't you be sitting there for many hours, if not days waiting for this
to synch up?

Do the wallets ever upgrade?

How often should you upgrade your wallet?


Thanks in advance again for my many questions, but when I learn something new, I like to learn it as best I can.
I also like to understand things in as simple and as efficient terms as possible.

[cryptotrade]

OK, I answered one of my own questions about location:

https://en.bitcoin.it/wiki/Data_directory

[cryptotrade]

So, correct me if I'm wrong:

 bitcoin is an application with data

AND it's a program?

There's 2 parts to it.

If that is so, then in order to efficiently keep your wallet, wouldn't you have to copy the program onto the flash drive
as well? 

Otherwise, how are you going to use the data on the wallet.dat?

Are you going to have to redownload the wallet program every single time, on every new computer, you want to use the wallet?  If so, that's a pain.


Another question - If I have my wallet.dat on a flash drive
and I use another computer that has the wallet program loaded onto it -
how do I get the wallet on that computer to recognize my flash drive's wallet.dat?


Wouldn't it be directed to it's own wallet.dat?


Again, this might be programming 101 to many of you, but to an average computer user, this is a mystery.

We need to break this information down into the simplest and easiest terms, so that everyone can understand bitcoin
and other currencies, otherwise we'll be in a Linux situation, where it's just too damn difficult and time-consuming for
most people to use and to trust.

As my best friend says, when I use my refrigerator, I don't need to be a refrigeration mechanic, I just plug it in, and it works.