Deleted the partition- How do I keep the gray screen from coming up?

[flick23]

I opened up a partition a few weeks ago b/c I needed to use a windows program that I no longer need. I was getting tired of having to hold alt-option to choose my HD everytime I started, so I deleted the partition. Now, I still have to go through the same process everytime I power up, even though I only have the Mac HD- I have to hold down alt/option when I start up and then click on the Mac HD button.

What do I do to make it go straight to Mac?

 

[miles01110]

Try selecting the OS X partition as the startup disc?

System Preferences -> Startup Disc

 

[flick23]

Thanks, that worked!