Startup / Shutdown Issues

[Robert E. Butts]

Fresh install of Ubuntu 6.06 Dapper; CPU is AMD Sempron.  After hours of
configuring, I've messed up both my shutdown and startup.

At shutdown, I only get the logout option; no halt or restart

At start, I get text-mode only; no graphical login.  I can manually
startx and get into gnome thereafter.

I'm inclined to believe my two problems are related.  I have no clue
what I did to cause this problem, and no clue how to fix it.

Any suggestions for how to proceed greatly appreciated.

TIA