problem booting computer

I have a lenovo desktop.  Turned it off the other night at work.  Turned it on today and it won't do anything except go into system recovery for Lenovo.  I go into system restore and restore to an earlier time (which works) but when I restart it goes right back into system recovery.  Any ideas on what to try?  I can't seem to get into safe mode either.  Do you know how to get into safe mode from the command prompt?  Can't do it by hitting F8.  This is a Win 7 Pro machine.
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Paul MacDonaldDirector, Information SystemsCommented:
Test the HD using the disk manufacturer's diagnostic utility. If it tells you the disk is bad, replace it. Also test the RAM using memtest86+, and also here, if the RAM is bad replace it. You'll find both tools on the UBCD:

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
i agree with rindi - your problem probably points to disk problems
**  you can make a bootable cd - or bootable usb stick of the UBCD

for completeness -here's how i handle disk problems :
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Windows 7

From novice to tech pro — start learning today.