After reading post after post of people experiencing the same Vista Sleep - no wake up issue - I was really sad. Just got a new Compaq Presario running Vista today for the kids. One of the bonuses was upgrading to a PC that WOULD sleep!
Anyway, in despair I clicked around and here's what fixed it (for now anyway)
Go to Control Panel
System Maintenance
Power Options
Click on "Change Advanced Power Settings"
Expand +Sleep
Expand +Allow Hybrid Sleep
Change this to "OFF"
I have no idea what Hybrid Sleep is - really don't want to know. All I know is that now when you put the PC to sleep - the thing sleeps and the power button changes to the expected orange color.
I can wake the PC up by pushing the sleep button or by pressing any key. The mouse doesn't seem to wake it up (its a tablet so maybe there's a thing going on there). But I can live with that compromise.
Hope this helps someone else!
