Lighting, Light Fixtures, Ceiling and Exhaust Fans - 12 wires in ceiling, 3 wires in light! help!

okay...
dear me, do i have a problem... in my 86 year old house, there has allegedly been electrical upgrades. now, in my bathroom there are two ceiling-mount wire boxes about 2 feet from eath other. one is just 'there,' the other is where i am trying to replace a light fixture. it is just a dome 3-bulb unit. the last one was basic too. the junction contains 3 sets of 3 wires( white, black and ground) and a fourth set of wires protruding from a thick black cord.(black white ground and a thicker cream wire) i can only assume all of these mean that there used to be a fan installed. so..... the first time, i attached all white to white (including the cream) all black to black, and the light ground to the other 4 grounds. the light came on with the breaker flip, but when i tried to turn it off it blew the breaker. tried it again after checking the ground (i thought surely, THIS must be the problem....) it wasnt. same thing happened.
now, i have capped off one white and one black both from the same bundle, leaving the ground 'grounded.' is this appropriate?
with the remaining 2,2,3 wires(not counting the grounds) how should i wire my light (my biggest concern is the cream colored wire) im sorry but brief instructions on a voltmeter could be useful, too.
also, is it safe to drywall over the useless hole? it used to be wired to a light which didnt work, and has since been capped off.
on the wall there is a double switch, only one of those switches worked the light, the other switch is a mystery.
any advice would sure be appreciated.
there is only so much you can do in a bathroom without light.
thanks, -Kristin

This job is about a thousand times easier if there was a working fixture in this location previously, and you know exactly how it was connected. Any chance that this is true?

Do you have any electrical test equipment? If so, what? If none, go to your home center and spend two bucks on a neon circuit tester.

John, I really appreciate this, and I do have good news for you. the fixture i am replacing did work. it was a2 wire unit(black and white) which had the fixture white wire capped to a short white wire capped to the white wires in the ceiling(i dont know if it was all of the white/cream) and similarly, black light to black ceiling. i have to admit i didnt get a very good look at it, im very new at this, and truely i have learned more from browsing this forum than i ever planned to learn about electricity. (so thanks again)
until i pick up the little doodad you speak of, can we speak hypothetically?

lets pretend that the 3 blacks are live and the 3 whites(including the cream) are neutral. i am sure the grounds are correct, so do i bundle all whites with 3whites from light, and all blacks to all blacks on light? or do i attach each white to a white on the light three times and repeat with the blacks to have 6 separate caps connecting the wires?
also, to use the current tester, can i turn the breaker back on with the wires bare and out of contact with each other? im afraid i wont have a choice if i want to know for sure which wires are live. i can try to give you a rudamentary diagram if it wil help: north
-------------------------------
(1) W,B,G
(4)CReam,B,G (black chord) (2)W,B,G

(3) W,B,G
-------------------------------
south
i have all of the G's grounded, and B&W(3) have been individually capped off and pushed away. (just to fit the remaining chords into my caps when the light is working) i can fiddle around with it until it works, but i dont want to fry my home in the process. when the breaker is off, the power outlets still work. but all of the lights in the back end of my house run from the same breaker as the bathroom light. i appreciate patience because i really dont want to throw in the towel and call a guy, but i dont want to wreck it, either. this is a life skill id sure like to have under my belt.
so!
using my hypothetical color code, and
if i want: the light to come on when the switch flips up
: the light to turn off when the switch is down.......
i do this......?
thanks again john, or anyone who can help!
-Kristin

Connect the new fixture exactly like the old light. Don't try to correct any color problems you think are there. If the old one worked and you connect the new exactly the same it will work also.

well, the problem is, that when i tried that (twice) i blew the breaker. (both times) the first times i hooked it up, i did it the way that i believe it was previously connected. i will try it again... this time i have cleaned up the wires so that i am 100% sure there isnt any hidden connections with the exposed wire.
thanks
-Kristin

okay, i tried it again....
all of the whites connected to the white light wires, the grounds are snug then the blacks connected to the blacks. flipped the breaker, and there was no action. the other lights to the breaker worked, but flipping the switch in the biffy did nothing. good news is there werent sparks or an explosion. now i am up for new ideas, if anyone has them.
all input is appreciated. thanks again, guys.
-Kristin

okay, boys: i got her done, using the process of elimination and ended up solving my prob in a manner no correspondance could have explained. not to say that i could have done it without you, because your forum is an excellent source for information. i will use it again, but for now i think ill stick to carpentry. thanks!
(happy dance)
-Kristin