HOw can i decrease the reserved recovery partition size

It sounds like your girl friend had everything prepackaged on the laptop to see that much drive space taken up from the start. Creating a working set of recovery disks would be the only way to work things out for that since you would end deleting the data from it by deletion or trying to reduce the size.

The set of recovery disks would be made up in case something happens to the hidden recovery partition itself. In this case once those were made up you wouldn't have to have that space taken up by that. The system could see a full restoration from the disk set instead. That 75gb is still quite a large chunk when most are about 10gb in size with everything compressed there for automatic restoration options.

Removing it is not a problem! Any good drive tool will delete any partition right off of the drive itself. But you also have to plan on losing the ability to restore the system to factory if anything happens to the disk set you make up from it there.

All that depends on whether or not you ever plan to restore the factory state as well as planning out a new partitioning scheme for the drive itself. If you are looking at a fresh install from scratch you would simply nuke the current partitions to proceed from there seeing the one or more new ones take the place of the original recovery and primary partitions seen.

If you are trying to preserve the present primary while nuking the recovery partition then you spend the time moving the primary to merge the now empty space since those are generally seen at the front of the drive. The thing about recovery disks made up is that they are still going to be bound to that one machine.

Any large swapout of board, hard drive, video card, etc. will then require a new disk to work with. Most of the drivers will still be found through the MS or other updates however.