I have started using the HTC Wildfire, and have a small niggle with it. When making a call, the screen blacks out to conserve power. This makes it awkward when you have to enter a number i.e. for an automated phone call response. Is there a setting to display the screen during a call?
What you're looking for is Screebl - a background service that monitors the phone's orientation, and based on that orientation decides when to allow the phone's power-saving features to operate.
There's a PRO version too that allows for integration with Locale amidst other extra features.
Also check out Shake Awake from Maplekey (in the market) - it allows you to wake the phone during a call with a shake.
I also think that pressing the HOME key should turn the screen on again. Try and let us know.
In your phone dialer enter the following sequence:
will show you Shutdown App configuration - you can choose to have the device power off directly instead of showing the menu for Airplane Mode / Power Off etc. when you long-press the power button. There's also an option for keeping the LCD on during the duration of a call.