Frozen On Screen

Or search nuvi locked on the garmin support site, and it will bring you to the appropriate fix.

Go there,  follow directions, fixed in three minutes.  It's a very common problem with the 30, 40, and 50.

Person above linked the directions, which was nice.  But the website has click to download the tools capability and the same directions

I got your back.

We've discovered a problem with the nuvi 30, 40, and 50 products that in some cases will prevent them from booting up successfully. A software fix has been released that will resolve this issue, please follow the steps below.

Things you'll need
• A PC running Windows XP or newer
• Your nuvi 30, 40, or 50 device
• mini USB cable to connect your device to your computer
• Access to your vehicle and power cable once you have completed the recovery process

Update your Software
1. Download and install the Garmin USB Drivers
http://www8.garmin.com/support/download_details.jsp?id=591
2. Download the Recovery Application and corresponding recovery file for your device, and save them some place easily found, like your Desktop:
download.garmin.com/support/firmware/nuvi_x0/Updater.exe
download.garmin.com/support/firmware/nuvi_x0/135000010260.rgn
o nuvi 40 and nuvi 50 Files:
  Recovery Application
  nuvi 40 and nuvi 50 recovery file
3. Drag and drop the .rgn file on top of the Updater.exe Recovery Application. The application will launch.
4. With your device disconnected and turned off, use your thumb to apply pressure to the upper-left hand corner of the touchscreen.
5. While still holding the touchscreen, connect the device to your computer using the mini USB cable.
6. The Updater program will detect your device and will list the device in the "USB Device" drop-down menu.
7. Click OK and let go of the touchscreen
8. Your nuvi will now go through the process of updating software. It may power off and on during this process. Once complete, your device may display the following message:
The software on the device is newer than the software you are attempting to install. Installing the older software will erase all user data. Install the older Software?
If this message appears, please select No.
9. Disconnect your device from the computer and connect it to your vehicle power cable while plugged into a live power outlet in your vehicle.
Your device should now be recovered and updated.

Still having problems?
Customers living in the United States or the United Kingdom can follow the steps below to automatically set up a repair for your product. Customers living elsewhere can Contact Us for further assistance.
1. Visit the Garmin Repair Center
2. Click 'Go' to enter your device Serial Number
3. Enter your Serial Number twice in the pop-up menu
4. Confirm your model number and Click on your device
5. Select "Power or Battery" as the Problem Category
6. Select "Locks Up, Freezes or Turns Off Unexpectedly" as the Problem Subcategory
7. Select "Frozen on Start Screen"
8. Enter additional notes describing your problem
9. Click Continue
10. Click "Yes" to submit a request for a repair or replacement?
11. Sign in to your myGarmin Account
12. Confirm your shipping address and e-mail, click submit
You will receive an e-mail within 10-15 minutes after completing this process. Please follow the instructions in that e-mail to complete your RMA.