It sounds like you have a bad hard drive or a jacked up file system. Try inserting your Windows disc (unless this is what you mean by recovery boot media, in which case you need an offline Windows repair disc), boot from it, and then get into the Command Prompt from the Advanced Tools menu. At the command prompt, type "chkdsk /r X:" without the quotes whereas X is the drive letter your hard drive currently has (most likely C but the installer sometimes does funny things so it may be D. That should either fix the issue or tell you if your drive is physically going bad.
The T400s uses a small, non-standard form factor hard drive and I've had them go bad fairly often before. You can get an adapter on eBay for around $10 that will let you install a 2nd hard drive in your optical drive bay. I'd consider putting a snazzy Samsung SSD like a 128GB 830 series drive in there and using that to boot, if it's fiscally an option. Hope this helps!