So I bought an Intel X25-M 80GB drive, plugged it in and installed Windows 7 on it. So far so good. But now I can't format my previous C drive with Windows 7 on it. In fact I can't boot from my ssd without having the other drive as the primary drive and selecting the other drive in the boot list. What do I do?
The bootloader for your new Win7 installation got put on your old hard drive when you installed it. The easiest thing to do at this point is to disconnect your old drive and re-install Win7 on the SSD while it's disconnected. Then, re-connect the old drive, copy off the data you care about, and format it (and put the data back on it if you want).