Well you should get silver if you can since it is free or use this site to download them. After downloading them follow the FAQ.
http://www.xbuc.net/
Also you should make sure the media ids are identical so the title update works. Since you might not be a pirate you won't be able to find the media id easily unless you dump the game or look at the disc which it should be there.
I usually transfer using xexmenu but this will work.
Update your XBOX 360 console to the latest dashboard version
Get yourself an usb stick with at least 1GB capacity
Format it as a XBOX 360 Memory Unit on your XBOX 360 console via 'Dashboard/System/Storage'
Connect your usb stick to your PC
On your pc, download XTAF (Latest Beta). Big thanks go out to Slasherking823 for this great app.
Run XTAF and click on 'File/Open Drive'. Now move to 'Cache Partition/Cache' and drag your update files into this folder. This will take some seconds.
Connect your usb stick with the XBOX 360 console
If you have a hard drive, open your Memory Settings and move the game title update to your hard drive, otherwise you are good to go