QUOTE(gman021 @ Apr 25 2008, 02:32 AM)

Did you make a back-up of the original textures? If not, you should use one if the above links.
Remember, always make a back-up of the original files if you don't like the mod! It saves you a lot of time and frustration!

Backups of the data folder wouldn't help in this case since they were using an overwrite. In the case of an overwrite, the game will always try to look for a file with that name in the datafolder for any game that was made while that mod was in effect. A datafolder backup would only help if you wanted to restore the look of that particular mod, not the look of the vanilla game.
Instead what you need to do is extract the needed files from the bsa archives and place them in the data folder at the right location. You can do this with BSA commander, or a similar program. The benefit to this is that should you decide to change your mind later, you can just alter the files in your data folder, and always have the files contained in the BSAs should you decide to change your mind a third time.
Although it might be easier to just make sure you have a good clean save to go back to, and to test out mods using that save, to see if they are what they want, before progressing further into the game. That way if you decide that the file is not to your tastes, you can remove it, use the clean save, and play as if nothing ever happened. The only thing to keep in mind with this sort of thing is that any auto-saves or quick-saves made while those mods were in place may not be usable. As these saves are constantly being overwritten, it is not a good idea to make it a habit of using them when doing this. It's much easier just doing that quest over again than it is starting from scratch, or figuring out how to stop changes made by a mod from remaining in your game. (paying attention to what is installed, or overwritten with mods helps out greatly here).