This phone needs AT&T coverage and in your area requires a 3G phone and LG 840G is a 3G phone, that's a good start.
If you decide to try it, LG 840G comes with 20 complimentary minutes. Use those minutes to see if it works for you inside your home and while driving around. Don't add an airtime card until you're sure you'll keep the phone. You have 14 days to return it to Walmart.
Verizon is a stronger network in your area. If you want to try the Samsung 380C, Samsung 390C, or Samsung Centura (an android phone), those are Verizon. They also come with 20 complimentary minutes to check coverage.
I'm currently trying out LG 840G with a strong AT&T signal but this is not the phone for me, feels cheaply made and the display is very poor. I'll be switching back to Samsung S390C which is better quality with many great features. I have good options because I can use either AT&T or Verizon in my area.