Xbox 360/live question

[twiztor | 851]

i'm trying to playSonic 4: Episode 2 via my xbox360. this game was download only.

my xbox won't stay powered on for more than a minute or two before turning off and/or restting. i assume this is an overheating issue, but i have the system in a wide open area so i don't know what's causing it. now here's some questions:

if the system overheated in the past (i don't know if it has, it's never caused me issues in the past but it is extremely rarely used), is there a way to solve this?

since i had to download this via xbox live, can i just log into my account from another system and play that way? for example, could i borrow a friend's system and still play my games?

last option, i know this game is available through Steam, but i've never used that and don't know anything about it. school me on what it is, how it's played, controllers, etc.

anything i'm overlooking? 

[DoctorEncore | 3,691]

Your account and games will migrate between systems, so if you can find another 360, you should be good to go.