Upload ISO 5.1 for iPhone 4 with old PC crash

[Tata]

I have IPhone 4, & used my PC as first time use, all data from PC transferred to my Phone ( ex: favorite on web..) now, my PC crashed, I can not use it anymore. My question is: how can I update ISO 4 to the new ISO 5.1. Without using my old PC? Can I use other PC to update it ? If so, do I lost data on my phone.
Please give me an advice
Thanks
Tatat