Heck I don't know what all the fuss is about I'm still running 4.1.9 just fine, it's patched and have not had an issue to date.
You should run 4.2.1 OR 4.2.2, if you do not understand how to make the errors not display then go with 4.2.1 however if you can add a snippet of code and/or tick the compatibility option in admincp to make them go poof then run 4.2.2 .
The newest version is typically (99% of the time) the safest and best to use, are there exceptions to this rule? Well sure why do you think I used 99% i.e. 1% of the time the exception is if an exploit if found in a vB4 yet vB3 is not affected by it, that would be one of the few exceptions.
^ LOL that explains it perfectly, and no, I do not intend to offend any in the Military, my father was in the Army most of my life, I was an Army Brat been all over to Germany, Georgia, Louisiana and more! Long story short Gary that's fine, you can want perfection in fact most IT and Website Guru's demand it themselves the only difference is they know how to implement it and make it work perfectly.... for someone who's learning vBulletin you must come to the realization that is not possible unless you dish out major bucks to someone who has the know-how to "perfect" it otherwise you must like I said a second ago, come to the realization your site is not going to be perfect until you yourself have the know-how to make it perfect.
/Salute!
With that background you have to be ok. I'm in no hurry so I'll add the snippet of code and wait for your style before I go back online. These Grandchildren have plans for me over the next week or so anyway.