Yes and no.
Yes it can be used as just a phone.
No it will not support any kind of data service at all. Don't even ask about it because the data service will not be available for it.
The main thing is that you need a Sprint CSR to over look that its another carriers branded phone in order to activate the ESN on their network.
All I need to do is simply make and recieve calls and make and recieve Text messages. The phone only says verizon on the battery cover, will that be a problem? And how can i do it and where can i get the ERI files and PRL?
As for text messages that is a shot in the dark. Most likely Messaging will not work at all.
There are huge differences in the file system between carriers and Sprint along with Verizon are the most modified to their own system. So getting any sort of data with a Alltel flashed VZW phone on a Sprint network will be probably impossible to do and that would include text messaging.
The best thing to do is Have a Sprint customer rep hook it up and see if it works.