New here and just a few questions about modding/iso's

Hi, im new here and i just got a few questions about iso's and modding and such, any help would be greatly appreciated

1)Im flashing my xbox and im just wondering if im going to have any issue's at all when the new dashboard update comes in november

2)Im making backups of some of my games and i want to know somthing about stealth patching, if i load an ISO up with XDVDMulleter and the checkmarks underneath the "Xtreme Compatability" are all checked, does that mean that its stealthed and good to go? and if not how do i check if an iso is stealthed/stealth it

if anyone could help me with these questions id appreciate it, thanks