This is for anyone is having a problem playing bf2.

I fixed mine and I had the following problems.

I got the error "The file d3dx9_25.dll cannot be found. Reinstalling this may fix the problem"

I tried putting the d3dx9_25.dll in bf2 folders,system32 folders and it got rid of the error, but then the screen would go black and then go back to desktop.

I thought it was a directX problem and I had 9.0b and I tried d/ling and installing 9.0c but I got another problem.

I would get this error "A cabinet file necessary for installation cannot be trusted".

1st step is to get Service Pack 2. Once you get Service Pack 2 for XP or 2000.
SP2 is Available to download free on microsofts website, just do a google search for it.

Then after you have that installed do the following.
Go to "Start" then "run" and type "cmd" without quotes and enter the following one at a time and hit "enter" after each one, if prompted click "ok".

regsvr32 /u softpub.dll
regsvr32 /u wintrust.dll
regsvr32 /u initpki.dll
regsvr32 /u dssenh.dll
regsvr32 /u rsaenh.dll
regsvr32 /u gpkcsp.dll
regsvr32 /u sccbase.dll
regsvr32 /u slbcsp.dll
regsvr32 /u mssip32.dll
regsvr32 /u cryptdlg.dll
type exit

THEN

Restart the computer.
Go to start, then run.
Type in cmd.
Type the following, pressing enter after each line:

regsvr32 softpub.dll
regsvr32 wintrust.dll
regsvr32 initpki.dll
regsvr32 dssenh.dll
regsvr32 rsaenh.dll
regsvr32 gpkcsp.dll
regsvr32 sccbase.dll
regsvr32 slbcsp.dll
regsvr32 mssip32.dll
regsvr32 cryptdlg.dll
type exit

The commands you type the 2nd time around are different they are minus the /u.

Then go to "Start" then "run" and type "dxdiag" if you still do not have 9.0c. Then go to the microsoft website and download and install 9.0c then download the 9.0c SDK June file, the file is 155mb and install that, then restart your pc. Uninstall Battlefield 2. Go to Control Panel, Add/Remove programs and remove it. Restart your pc.

Then install it and try to run it. And you will be happy.