File permissions - "root concern"

I'm at an institution with many users and a few system administrators on a network of mainly linux and a few unix machines. I have a two-part question.

1) Can a root user *read* the contents of a text file that I've set to be readable only for myself? (I thought it might be possible that root could *delete* any file, but not read it).

I'm concerned because I'm wondering what the best way is to make a personal text file of mine ONLY readable by myself - but preferably in a way that's simple, because I read and edit this file often.

So far what I've done is simply reduce the chances of its detection by putting it in a directory with a name beginning with a dot '.', which means it's not immediately visible, and also naming the file itself dot-something. Of course the directory and file itself are both only read/writable by myself.
How safe is this method?

Let's pretend I don't trust the system admins...can they snoop around and read my file if they somehow manage to find it?

I suspect the answer is yes.

IF so, then:

2) Can anyone suggest a good way to simply & quickly encrypt a text file so that only I can read/edit it?

Any suggestions that are really SIMPLE would be appreciated - I mean, something that can be incorporated into a simple script so that I can read/edit this file without much hassle. I edit it every day, and it's also extremely important to me, so I don't want to worry about silly errors like "crypt" creating a copy of the file and then deleting the original - but the copy didn't work, say...and then the file's gone! Or is there a simple and 100%-safe way to use crypt?

Thanks a lot for advice!!

File permissions - "root concern" - encryption?