my advice: try to dedicate more than 3-4 hours a day if possible, esp if you only have a month to study. try more like 8-10 hours.
as far as materials go, the destroyer is incredibly difficult and really makes sure you know your stuff, but quite possibly overkill.. kaplans book is a good place to start.. once you've read through the bio parts and have a good grasp, i recommend a cliff's AP bio book.. it's a really good supplement to kaplan's info, which is lacking in some areas, especially bio.
for the PAT, RC and QR, i recommend practice, practice, and umm.. more practice. get as many mock tests as possible and it helps if theyre on the computer and timed. do several full lengths.. i also suggest Crack DAT Math and PAT, both of which i found to be more difficult than the actual test.
best of luck!