I'd advise a complete startover. I'd uninstall the game, delete any existing
leftover files like game configuration, settings (the uninstall process should ask you if you want to). Choose Yes.
Then I'd recommend a video driver cleaner from here:
Driver Cleaner Professional download from Guru3D.com
Corrupt or messed up video files can often cause problems. It's best to start fresh again.
Download the driver cleaner, the latest Nvidia video driver for your card. Wouldn't hurt to defragment your harddrive too.
Install DriverCleaner and run that, install the video driver, then reinstall the game..and patch it with the latest patch for BF2142.
As for game disconnects, it could be anything. Mostly likely your connection, firewall, router or the game needs proper patch. 1.40 > 1.09 (1.4 vs. 1). See?
Before you tackle Problem 2....
get a fresh start. Set your game settings lower if you still have trouble.