Old homeowner left this fertilizer....Should I use it?
yes, those will work fine, fertilizer doesn't really go bad, unless it gets wet. then it is just clumpy and hard to disperse. The NPK ratio seems like a solid season opening blend, but make sure you don't do it when its 75 and hot. if you see a nice little rain on the weather channel, go ahead and spread it out there. it will definitly green up your turf. as for weeds, KILL 'em all. go get a selective herbicide and go at it.