BOOTLDR: C3750 Boot Loader (C3750-HBOOT-M) Version 12.2(44)SE5, RELEASE SOFTWARE (fc1)
12.2(25)SEE2 is the IOS version. 12.2(44)SE5 is the boot loader version.
Some (but not all) IOS releases include a boot loader upgrade which is automatically installed when the image is first booted. That is why in the output above the boot loader version has a higher maintenance revision than the IOS image, because at some point in the past it was running a newer release and the boot loader was upgraded.
It is expected that the boot loader and IOS version strings differ and this is not something you should be concerned about or need to manage.