Startup failure

Since I installed NIS (19.9.1.14) on my Dell, Windows XP (version 5.1, build 2600, service pack 3)  I am getting a little blue message box telling me that I should change my screen resolution.  Nothing I do makes that go away.  But the really annoying thing is that sometimes, maybe 1 in 5 startups, I get the opening Windows XP screen, then the full blue screen "Welcome" window, and then nothing else.  It stalls on the Welcome window until I power down and restart.  Has anyone else had this?  Any ideas as to cure?