How to come back to start menue with e-mails

My starting menu e-mails diappeared and I do not know to get them back

Check your parameters
Menu-Tools-Settings    General     “Show on Startup”   Inbox

Where can I find this show on start up? I am a computer nitwit

If you are on Version 7

Top left corner is MENU
Then select option   TOOLSs
Then select SETTINGS

Look for General   as it should be the first screen you are presented with

About 7 down from top is the option    "Show on Startup "  
It is a pull down   and it should be set to inbox.

If it not this  then you need to explain in more detail what is happening