Don't know what crashed my system, but upon trying to reboot I receive
the message invalid boot sector, and then one other time, [the first
time] the message was: please type in name of command enterpeture,
which of course I
didn't know what to do. I thought I had made a rescue disk, but my mom
was dying and I guess I didn't, so now my hp pavilion zt1135 is
totally useless unless u can PLEASE HELP ME! I would be willing to
pay much more for this answer, but right now I just can't.
I'm 67 and living on a very limited budget, but will be more than
happy to pay 20 as soon as I'm able. Thanks for any and all
considerations to my request.

shuqualak...

DIYdataRecovery makes a program called Disk Patch, which sounds
like it will do the trick. Explanations and instructions are here:
http://www.diydatarecovery.nl/~tkuurstra/boot.htm

The program description is here:
http://www.diydatarecovery.nl/~tkuurstra/DiskPatch.htm

The Demo download is here:
http://www.download.com/3000-2094-10063613.html?part=75277%2520&subj=dlpage&tag=button

You may have to pay to activate the program before it
is capable of repairing the boot sector, but the demo
should let you know where you stand.

The 'command interpreter' is a file called command.com
but if your boot sector is damaged, this just means
the operating system files are not being located.

When you attempt to boot your system you get "invalid boot sector" 
then, as it says, your boot sector of the harddrive is probably
corrupt.  I am not sure Windows can overcome this harddrive error or
not.  If it can then this is what I would do.

Try booting to "safe mode" by holding down the F8 key on your
keyboard.  It will take you to a menu option that you can choose safe
mode.

Once in safe mode you can run "system restore" to fix the boot sector.
To do this go to the START menu programs - accessories - system tools
- system
restore.  Pick a restore date that you know was before the time that
you had this problem.

If this doesn't work, you might need to bring it somewhere to get it replaced.