Macintosh: Upgrading to Lion

Hi,

1) I am used to with Microsoft Windows OS (XP, Vista, 7, etc)
2) I have to upgrade a Macbook (which is at "Snow Leopard" --> Mac OS X v.10.6.8) and a MacMini (which is at "Leopard" --> Mac OS X v.10.5) to Lion (Mac OS X v.10.7)
3) I need the confirmation and suggestion from Experts accordingly
4) My manager has confirmed me that he does not want a "Clean Install"
5) The things that I plan to do as the followings:
i) Downloading the installation files for LION from: http://www.apple.com/macosx/ with the MacBook
ii) This Installation files will be in the "Application folder"
- I will copy this Installation files to my flash drive
iii) Before Upgrading to LION, I want to create 2 things (Creating the Bootable Lion Install DVD and USB Drive)
iv) To create the bootable Lion Install DVD drive
- I will get the installation file from my flash drive (please see # ii)
- and continue from there
v) To Create the bootable Lion Install USB drive
- I will also get the installation file from my flash drive (please see # ii)
- and continue from there
vi) For MacBook
- I will update to Lion by executing the "downloaded file" (please see # i)
- I do not need to use the bootable Lion Install DVD or USB drive

vii) For MacMini
- I have to download files to upgrade from Leopard to snow Leopard from here --> : http://store.apple.com/us/product/MC573Z/A
- After this machine will be at snow leopard, I will use either the bootable Lion Install DVD or USB drive which i have created it above

6) My questions: I am still confused. I am not sure that the above procedures are workable. I need the confirmation and suggestion from Experts please

7) Thank you

tjie