My g1 phone wont start up

your phone booted up into the g1 bootloader screen, if you want to be able to use the phone again you will have to probably push the rc29 recovery.img then manually upgrade back to whatever rom you are on

P.S you will lose your pictures but you wont lose your contacts because once you sign in to gmail on the phone it automatically retrieves the contacts that were on the phone

P.P.S you will lose root capability if you had it