Are you in the US? If so, I suggest you install the Sunset version of Money and use that to open your file.
If you are not in the US, then be glad this came up now rather than a year from now.
Find the sample.mny file in your install folder. That may be
"C:\Program Files\Microsoft Money 2005". Copy sample.mny file to
your Documents folder in Win7 or Vista. Right-click the Money start
icon and select RunAsAdministrator. Click File->Open and browse to
that sample.mny file. Money 2005 will do an update. Close Money.
Reboot the computer. Then open Money and check that Help->About...
says you then have version 14.0.*.1105.
Make sure your .mny and .mbf files are in your Documents folder.
Then you should be able to File->Open or Restore your existing
files.
If restoring a backup, do not restore Do not restore to the default
location. Instead Browse to your Documents folder, and select a
name. Then change the backup locations shown in
Tools->Settings->BackupOptions to locations that exist on your
computer currently. Consider your backup strategies; disks fail.
See http://money.mvps.org/faq/article/630.aspx for a method of
making a self-contained disk for reinstall of Money 2005 with the
updates in place. Be sure to do this before end of January 2011.
Do not lose the disk.