Is there any underlying rule for usage of I/me/myself?

Regarding "myself" and "yourself": in the UK at least these are heard increasingly where "me" and "you" would usually be used in an attempt to sound more formal. Some people recognise there is a rule that governs when to use I/me/myself and that using "me" is frowned upon in some cases, but they don't know quite what that rule is. So you hear sentences like "If you could phone myself back later" or "I'll pass those on to yourself".

"Me and X" as a subject is perfectly fine in informal spoken English, but "I" should always be used in the subject formally.

"I" should only be used in subject, using it for the object is a hyper-correction from people constantly being told "Me and X" is wrong.

I am a native speaker.
'Him and I wend to the store'

Caspian, there is precious little that is NATIVE about your typing though. :-)

By the way, I always knew it should be, "He and I went to the club". Why do you think only native speakers would know that.

Dan

google search

''it's you and I'' 39.200.000

''it's you and me'' 553.000

"Basically, nobody will look down on you if you say "himself", but many people will if you use "hisself". "

That's true unless you are joking about a snake.