Problem with Windows 7 Ultimate 32bit installing.

Hi to every one!
I'm Artan and i have a old Fujitsu Siemens PC Scenic BS015 with a P 4 2.8 GHz. and 3 GB DDR with HDD 37.2 GB.
Was installed on it the Windows 7 Ultimate 32 bit. I find another HDD of 37.2 GB and i put on to extend dhe HDD. After some times the PC was not working well and I thought maybe is time to re install the Windows 7.
When I try to do so was impossible to re install the OS on the Drive C (where it was) but automatically offers me to install on the other Drive (). I done so but I have now two OS on my computer and I don't need both of them.
Can somebody help me how can I fix this problem?

Did you merge the two HD's into a RAID array? Your PC may or may not have a RAID utility or setting in BIOS setup.

Either way, Delete all partitions during the booted install using the Drive Options pictured in Steps 7 and 8 of Clean Install Windows 7.

Then either create and format a New partition there using the same Drive Options, or just click Next and the installer will do it for you.

If this isn't enough then complete the rest of the steps to Troubleshoot Windows 7 Installation Failures - Windows 7 Help Forums