I was not able to totally uninstall Webroot. However, a curious thing happened yesterday. I decided to travel around to other regions and noticed there were almost negligible texture issues wherever I went compared to my home region. At that point I deleted those settings that were advised previously. Lo and behold, after I signed back in to SL everything was working normally. Go figure.
Within the last 30 days, I have been experiencing frequent texture corruption, as well as log in failure with the message that my region is logging out. Also, no matter what viewer I use, SL crashes and stops working.