try reinstalling, but before you click "install now," hit shift+10 to bring up the command prompt.
at each prompt, type the following:
- list disk
- sel disk 0
- clean all (this will erase and overwrite the entire HDD, zeroing it and will take a long time)
Then proceed with setup.
if you don't want the system reserved partition, you can:
- click drive options
- create one partition
- delete the 100MB system reserved partition that windows creates
- continue with setup
Gparted is an excellent tool, but in this case likely to be akin to using artillery to kill a fly