How Can I Download All Text Conversations From The Iphone To A Pc

I’d like to keep text conversations, but not on my phone anymore. How am I able to transfer months and months of text chats (some photos attached) to my PC, without worrying that I’m going to lose information? Any information on this one?

I’m on a 3Gs, 32Gb with 4.2.1 iOS.

Thanks for any help you can provide me with ahead of time.