fill my work room walls with great photos.
get a smaller work room
I expect you will want to use cs4 for editing - if so that in itself is fairly complicated, with a rich tapestry of corrections and effects, etc.- as in acr. It maybe that you find qimage's comparative simplicity more to your liking wrt raw processing, but as with most things you get out what you put in. Of course, with the "is being improved with added features coming along rapidly in each update" that will ultimately end up complicated too - but that's not here and now.
If your photos are 'sort of average' wrt exposure, etc., then the in camera jpg may well be as good as you will need to get, and qimage will probably get you there from a raw file. However if you need to push things around more, then acr will be the way to go, since there are more precise/specific controls available to the user - you just have to learn how to use them.
If money is tight, then stick with acr, (there is actually plenty of good training videos and tutorials for free - maybe you've found the rubbish ones) and if you are not concerned about canvas wraps, etc., then get the cheapest qimage available just for printing. That will keep your workflow simple, you will not be getting a mix of 'sidecar' files, etc. Alternatively, there are ways of upsizing in cs4 which will be good enough for the size of print you can handle, but possibly there are some other 'must have' features in qimage that you think you need. Easy way to find out - as Fred said - download the trial.
Best wishes,
Ray