I have just registered so i apologise if this is already common knowledge but i just sussed this problem out an hour ago.
I wanted to install my newly bought copy(dvd) bf2 on a mates pc and of course being a newb to this i didnt know it wouldnt work!
But this is what DID WORK.
On the second pc:-
Install the game as normal from the original disc.
Then install alcohol 120%(for free), run the create image utility with the original dvd in the drive,you have 2 files converted to the chosen destination(1 a larger mdf,and a very small mds file)
Next install the free Daemon tools utilty and use the find image function(search in the new file location),it will show the larger mdf file if all is correct,add or ‘mount’ this file and it will create a virtual drive with which it can be launched from(it will appear as a 2nd dvd drive in your computer)
Now your done,just remove your dvd and launch the game from the usual desktop icon and voila! game plays with NO DISC NEEDED!