None of my old riding clothes fit, any recommendations for loose fitting stuff that would "hide" me a bit?
Get one of the cheaper Pearl Izumi bibshorts in a larger size and wear the loose fitting Under Armour shirts over them. You can find tons of options on amazon.
I have a 2008 Cannondale CAAD 9, is it capable of someone of my weight?
No problem with this bike at your weight of 225. If you start breaking spokes, you might need a good set of clyde road wheels like the Williams 30x.