You are trying to install XP from a flash drive? I have some comments
1) While a more detailed description of the process you are using to try to reinstall the OS and what unexpected results happen would be useful, at a guess you are trying to boot from the flash drive and the BIOS is not seeing it to boot from. If you are familiar with BIOS, go in and look for the flash drive and make it the first in the list of boot devices. If you are not familiar with BIOS, ask here to get more detail.
2) XP is distributed on discs (so long ago I have forgotten if they are CDs or DVDs). Do you have the original distribution? It's much better to boot from that.
3) Did you have any data on that disk / partition that you need? There are tools that can help you grab data off a formatted or erased partition. They are slow, but generally work unless you did a secure wipe. If you re-install the OS on that drive, the chance of any of those tools working goes down to slim-to-none.