(see solution/workaround for texting issue below)
I'm 100% in the same boat as you.
I have not found a fix for the screenshot issue yet, but as soon as I do I will reply to you here (i'm determined to find one because its really been ******* me off).
Ever since the gingerbread (2.3 eh03) update I've been having all the same issues you describe (txts dont send, dont receive on time, keyboard locks up in messaging app (standard android keyboard, not swype) - in an attempt to fix this on my own, i cleanly formatted my SD card and ran the factory reset utility from settings. The phone would not even boot at that point (stuck in a loop). I took the phone to Verizon (just to see what they would say) and they said they could fix it - came back an hour later and the verizon employee stated he couldn't get the phone booted back up and since it was no longer under warranty, I would have to buy a new phone (which is completely incorrect, the phone was rendered useless based on an update VERIZON pushed out, it was not faulty to do manufacturer defects, standard wear and tear, and/or abuse by user) So the warranty excuse would not apply here. Rather than fight it, I still wanted to get this working to prove a point (i'm an IT guy). So I took the phone home, loaded up Odin and restored the phone to a stock Verizon 2.3 Gingerbread ROM.
After getting the phone cleanly working again, the issues still persisted (problems with txts, keyboard in messenger app, auto screenshots) - so, I downloaded Handcent SMS (a free app you can download in the Android Market/Google Play Store). Suddenly, all my texting and keyboard issues went away. What this tells me is there is a problem with the STOCK SMS/Messaging app with the Fascinate since the 2.3 update. VERIZON NEEDS TO ADDRESS THIS SO MANY OF THEIR FASCINATE USERS ARE HAVING THIS PROBLEM. Again, the problem is not with the service to the phone, but the stock SMS app of the Fascinate itself (the stock SMS app background service will 'freeze', and the only way to send or receive a txt when that happens is to reboot the device). The keyboard issue also went away after moving to Handcent SMS. Keep in mind, Handcent SMS is highly customizable, so when you switch to it spend some time getting used to it to make it work the way you want it to.
One other point I'd like to add:
Any user that has a Verizon Fascinate should be documenting all of their experiences with Verizon and officially file a complaint with the Better Business Bureau (can be done online via the BBB website). After my recent experience (my trip to the Verizon store was FAR from stellar) something really needs to be done here. We as customers pay good money for these phones, only to have them rendered useless by poor updates and firmware which we as the customer have no control over (well, we do, but not without voiding the warranty of our phones). But if we don't get support from Verizon, what's the benefit of not breaking our warranty anyway? Point is, Verizon is dropping the ball on this one with all their Fascinate users by NOT addressing these issues which have so clearly been brought to their attention. They should be clearly communicating these issues to their staff and have a process and plan in place to MAKE THINGS RIGHT for the folks having these issues. Shame on your Verizon....