I would change the building specifications.

I would add SOO MANY TRIGGER CONDITIONS AND ACTIONS!!!
TONS OF!
Detect everything what you can do @ scbw
that would be sooo awesome....
yea... let me dream please....

Let people center locations on Scanner Sweeps, make Distruption Web/Dark Storm belong to the casting player, add conditions to read units' HP/shield/energy totals, update some of the graphics, and make patches not fuck DoA.

I would add them for example, even more like:
-> change minerals on-hand
-> Disable/Enable Burndown for Unit/Building
-> Disable/Enable zerg-regeneration for Unit/Building
-> Disable/Enable Plasma-Shields for Unit/Building
-> Disable/Enable Plasma-Shields regenration for Unit/Building
-> Set the speed of regeneration / burndown of any unit
-> change attack speed
-> detect bullets
-> let CPUs do whatever you want
-> add buttons like "build geysire" (Datedit...)

and many many more...

I would leave StarCraft alone, because I realize that StarCraft 2 will eventually come out within a year or so, and are smart enough not to tamper with copyrighted material.

Starcraft2's editor is awesome
the game itself.. isnt that good as SC (as I think)
and... if you COULD

What does sc2 editor do?

ima not able to list all features down here

Basically anything that you can code.
Which is everything.

I would make the game all High def with like 1920x1200 resolution. (but still 2d)
increase the capabilities of the editor
ability to make clans

I would bring back the sex box in profiles.

Nah, I would implement a mind-reading feature that translates brain waves into a map, that way I can be lazy and make maps at the same time!

I would have a fourth race. Something cool.

Revive and kill Fenix another 39 times.

Remove the bug that won't allow us to start a sentence with "or."

As an editor, i'd like to be able to play edits i made in the editor right away while in the game.

Or test the map inside the editor

(Stronghold series)

I wouldn't change a thing from Starcraft, it's great as it is!

but the editor... isn't that good.... I would let starcraft untouched, yea it rocks (maybe not the emdic, but whatever)
the editor can be updated.... easily as I think...
blizzard really should make an Editor-Patch which adds new features etc.

Agreed, the editor should be more "flexible". I was just saying that the game is great.

I would change the zerg so that thought could reasonably infest many things. I would also make the creep give zerg an advantage and take away their defensive buildings. I would also like to see the creep being something you have to keep at bay and push back in a campaign level.

I'd also let players use macros. I'd like to see epic battles between 'purist' players (who do everything themselves through high APM) and scripters who spent days coming of with algorithms that are ready for anything. Think Boxer vs Zynastor.