Sorry for my grammer first im not englishman ( in NY ) 
At first you must check does your BIOS support option boot from removeble media ( some other thong accept hdd an CD ). In BIOS check options 'feature settings' or 'advanced setup', if you cant find anything update your BIOS and if you cant find it and after that sorry your BIOS does not support that.
Next step is to find good tool which will enable booting from flash memory. On that purpose it will help ”HP USB Disk Storage Format Tool” he is produced for HP memory drives bit it also work good with every other.
After instalation, start up program, select memory which you want to format, sys type FAT, and select option “Create a DOS startup disk“. If you are using Win XP necessary DOS files you can download here http://people.umass.edu/oaaltone//HPUSBFW_BOOTFILES.zip
After instaling all files and formating memory, she is ready for booting. Restart system come into BIOS select boot from removeble media. If you want to flash BIOS from that memory drive ounly thing you must do is when you are in Win copy program for flashing BIOS and new BIOS.
good luck del_

At first you must check does your BIOS support option boot from removeble media ( some other thong accept hdd an CD ). In BIOS check options 'feature settings' or 'advanced setup', if you cant find anything update your BIOS and if you cant find it and after that sorry your BIOS does not support that.
Next step is to find good tool which will enable booting from flash memory. On that purpose it will help ”HP USB Disk Storage Format Tool” he is produced for HP memory drives bit it also work good with every other.
After instalation, start up program, select memory which you want to format, sys type FAT, and select option “Create a DOS startup disk“. If you are using Win XP necessary DOS files you can download here http://people.umass.edu/oaaltone//HPUSBFW_BOOTFILES.zip
After instaling all files and formating memory, she is ready for booting. Restart system come into BIOS select boot from removeble media. If you want to flash BIOS from that memory drive ounly thing you must do is when you are in Win copy program for flashing BIOS and new BIOS.
good luck del_