Microsoft MyPhone irreparably messed up my phone (?)

I’m not positive but nothing has been the same since I installed it.
My phone is a Motorola Moto Q9c from Alltel, which means I just now got switched to Verizon. I don’t know enough about phones and networks to know if that would have anything to do with it.

I installed Microsoft’s MyPhone, which is an online backup utility type of thing for your phone. Since then, whenever I do certain things, my phone slows way down, almost to a freeze. I say almost because, if I wait SEVERAL minutes, it will at least speed up enough to be barely usable. The ‘certain things’ include sending text messages or emails – I can RECEIVE them just fine, but, if I compose one it will start the slowing problem within seconds of sending. Also, if I attempt to DELETE texts, it happens but not if I delete emails (the email is a gMail account, which is accessed by the native messaging client via IMAP). And, the other one I’ve noticed is if I change anything in the tasks list – if I add a task, delete, or even edit, it will begin the slowing problem.
Again, just to be clear, all three are built-in apps.
In all cases, I have to yank the battery to reset it. But, this doesn’t take care of everything – for instance, if it happened because I deleted texts, the texts will be back. Yet, this doesn’t happen every time – but most of the time.

I did uninstall the MyPhone app but the problem is still there.

So, my theory here is that MyPhone – which does a backup/sync to their server of various things, including texts and tasks – is monitoring for changes and then logging the change or something like that and that is where something is not working the way it’s supposed to. And/or it is not getting along with some other app I have installed. I am guessing this is a change made to the registry that was not reversed when uninstalled. Again, I know very little about phones, so this is just slightly informed guessing.

As an experiment, I re-installed the app and went into settings and unchecked the boxes that said to sync messages and tasks – my hope being that it would make a new registry setting that would not cause this when uninstalled. I then once again uninstalled, but the problem is still there.

I have googled this as best I could figure out and can find no one else making this complaint. So, it seems my only choice is to reset the phone to factory state, which is really going to suck, but I have tried everything I can think of.

Any suggestions would be appreciated.