|First test memory with Memtest86 since some of the symptoms you describe could be a faulty RAM stick. Not errors are acceptable. If you get errors, retry with one stick at a time to find the problem stick.|
Once you are sure your memory is good try again recovering from the built in recovery partition. This should install the boot partition properly but if it does not you can then do a start up repair. THIS you can do from a Windows 7 Repair Disk you can make from ANY Windows 7 machine that is also the same (32bit or 64bit) and this will replace the boot partition. If this did not work you MAY have a hard drive problem but try the proper factory recovery disk set first (you would need this anyway if you need to replace the hard drive) to reinstall the OS (full format if you get the option). The best test for the hard drive would be from the hard drive manufacturer's downloadable utility.
You have to be a little bit crazy to keep you from going insane.