Ok gopha I still think its a problem to do with old BF2 files being around and causing problems.
I just googled BF2 installation problems and got a thread where people were talking generally what went wrong. Summary of what they think cause problems.
http://www.techspot.com/vb/topic33268.html
Plus I looked back at when I was having problems getting the game working. Once it stops it can be annoying to get going again. Here's my old thread....
http://archive.thehavennet.org.uk/viewtopic.php?t=1845
* Any Registery inputs left after uninstall need to be deleted.
* Make sure you delete the whole BF2 folder
* Check in the Mydocuments area for the BF2 folder there and delete that.
* Check for the Installshield Information folder for BF2 and delete that too.
Then do fresh install.
As for install Order I got this list from here
http://forum.eagames.co.uk/viewtopic.php?p=132216#132216
Ok it goes like this:
If you just have Battlefield 2 then:
1) Clean Installation of Battlefield 2
2) Install 1.22 (full) Patch
3) Play!
If you have Special Forces then:
1) Clean Installation of Battlefield 2
2) Install Special Forces
3) Install 1.22 (full) Patch
4) Play!
If you have Euro Force then:
1) Clean Installation of Battlefield 2
2) Install Special Forces (if you have it)
3) Install 1.21 (full) Patch
4) Install Euro Force
5) Install 1.22 (incremental)
6) Play!
You only need to install the 1.22 patch Once, if done as above, depending on which game(s) you have.
Hopefully I haven't missed anything out.