If you have a Mac, try smart converter. Its free and supports many formats.
It depends on if you want SPL or SQL. once you decide that it can be easier to narrow down.
Fianl Cut Pro. Easy to use and alot of tutorials to get you up to speed
definetly a Mac, the editing software available is unbelievably better
Windows 7. Windows 8 isn't ready yet. Not alot is compatible yet and you would have alot of headache just trying to navigate. XP is being...
MXPlayer for mac definetly!