upgrade this old MacBook Pro to mountain lion? I have an "old" MacBook Pro with the following specs:

Modelname: MacBook Pro
Modell-Identification: MacBookPro5,4
Processor type: Intel Core 2 Duo
Processor speed: 2.53 GHz
processer count: 1
core count: 2
L2-Cache: 3 MB
Memory: 4 GB
Bus speed: 1.07 GHz
Boot-ROM-Version: MBP53.00AC.B03
SMC-Version (System): 1.49f2


It currently runs OS X 10.5.8 and seems a bit laggy from time to time, which might (also) be due to the loads of crapware on it.

I have a two part question now:


What would be the recommended maximum OS X version I should upgrade this machine to, so that it still runs nice and smooth? Is mountain lion safe?
How do I do a clean (full wipe) install of the system, since the latest versions of OS X do not come with a bootable disc anymore?
The second part is trivial, install Lion or Mountain Lion and let it upgrade everything. That will create a recovery HD where you can then reboot and erase the main volume. If you save the installer after the first download, you can avoid the download the second time.

My experience is that the performance of older computers is as good as or better than the old OS - especially when you are erasing things and migrating files over later (or by hand) as much support for older systems was dropped making Mountain Lion fairly streamlined and responsive.