Okay, I have just finished the mission where I had to go though and kill all the bad dudes in vault 3. after that i went to the brotherhood's hideout and talked to the elder. I saved manually and it auto-saved in about the same spot. I exited the game and later tried loading the auto save. upon loading the game CTD. So i tried the manual save with no luck. Then i tried to load an older save file that i had. this one worked. So does that mean that i have two very currupted save files on my computer or is there something that i can do to get it to work. PLEASE HELP ME. I really don't want to start over from my old save point.

Similar to the Come Fly with Me quest, many (albeit less) people are saying that Vault 3 is causing corrupt saves as well. If your files are corrupted (which it sounds like they are) you will have to replay with your old save file. Yes, it svcks.

Having the same issue, seems that Vault 3 and Repconn Test facility are causing saves to CTD when loaded. Hopefully a new patch will come out soon to fix these issues...