I like Methot, just not sure about giving him a big money, long-term deal at his age with his recent injuries. If I remember correctly we let Volchenkov go for the same reasons and it worked out pretty well for us.
Perron would be a solid return. Even the Oilers couldn't stop him from putting up 25G and 55P last season. On pace for 40+ points in an embarrasingly bad start for the team this season. He's a 50+ point forward in a normal season.
If we can find a way to get rid of Greening in the deal, and maybe pick up an asset in the deal as well, it should be a no brainer:
Methot + Greening for Perron + 3rd.