|Can't understand why you messed with the recovery partition id number.|
The 'EISA' partition is the one that contains the recovery data for the original pre-installed version of Windows. If it's showing '100%' free it does not necessarily mean the recovery data has gone as some disk tools cannot read the data on a recovery partition so they just report it as having no data on it.
However, it could mean just what it says - it's 100% free and the recovery data has been wiped. If 'F11' does not work any more, chances are the recovery data has gone.
If it's gone, the only way now to do a recovery is hope that the owner has made a set of recovery DVDs for it, because he won't be able to make them now that the recovery data has gone. Glad I'm not in your shoes!
Depending on the maker, you can sometimes buy a set of recovery discs from them via their website or phone number but you'll have to pay for them.