jailbreakme.com should have no effect on 1.1.4! however it can leave files which can cause problems with some other functions when you UPDATE.
You must have jailbreaked some other way on 1.1.4?
The only methods are ZiPhone or Independence.
I suggest you search on installer for youtube activation and try that and if that fails then restore and jailbreak again.
Yahoo mail has nothing to do with the jailbreak that is simply down to a wrong password or setting somewhere. If however nothing works to fix BOTH of the issues then.
RESTORE to 1.1.4 and DO NOT use your back up but set up the iPhone as a new phone then jailbreak again and it will definately fix the problems.