XP Pro: How do I SAFELY Install the SAME Game Twice?

[Steady Teddy]

This might be a topic for the Gaming section but I think it could apply here since I'm worried about perhaps damaging my Registry or causing conflicts from identical Games/Programs.
I'm trying to install a game (F1 2001 by EA) a second time on my hard drive. The reason for this is because I've already modified the original installation of the game that it's gotten to the point where I can't modify it any more. With the second installation I would be able to add more mods/updates.
I tried installing it a second time but instead of doing an automatic installation into the default folder -Program Files/EA Sports/F1 2001- I created a different folder titled "F1 2001 Mods" and installed it into Program Files/F1 2001 Mods.
The installation process went smoothly (at least I think it did) but when I tried starting the game it crashed to the desk top. I could not start the game at all. Shortcut Properties Taget was correct so I don't think there was a problem there.
F1 2001 was not listed in Add/Remove Programs twice so I could not remove it and try starting over. I used Sys Restore before installing F1 2001 so I decided to DELETE the "F1 2001 Mods" folder (BIG Mistake!) and go back to the Restore Point before installation of game.
System Restore was unable to go back to that restore point or any other restore point for that matter. I suspected that I corrupted my Registry so I decided to perform an XP Repair.

Things are back to normal so far. I haven't tried to reinstall the game but I know that many gamers have multiple installations of the same game on their hard drive. How would I do this safely and properly??

Should the game be installed in the Program Files Folder? If not, then where? Would I have to rename the game altogether to get it to work??

Again, I apologize if this thread should be in the Games section but I think it could apply to any Program that someone is trying to install a second time. Plus I'm guessing that the people who frequent this section of the forum are more knowledgable on matters such as this.

Thanks in advance