Party with most seats would be able to go for a minority govt, but if that was the tories, they'd know they don't have support from Labour or the SNP, and not much from the Lib Dems either, so I doubt they'd want to try. Labour would have more success, as the SNP and Lib Dems would probably agree with them on a lot of issues, so it could be done.
Correct. It all comes down to the Queens speech. In some respect it's not so much who your allies are, more who your enemies are. Cameron has a lot more enemies than friends.