The best thing to do is to have a hard drive dedicated to storing the renders. Yes, when you do frame rendering, you have lots of frames; thing is, you still have this when you render to video. They are just stored in a pseudo temp file, then compiled after completion into the selected video format, then deleted ( this is the danger; if the render bombs for any reason, if you run out of scratch space on your system, if the power flickers enough to cause the OS to so much as hiccup, you lose all that was done, and have to restart the render from scratch). You want both enough space that running out of space won't be an issue, and a place to save projects until you archive them.

The frame level adjustments are limited to whatever image editor you use is limited to. If Paintshop Pro, those are your limits, If Photoshop, ditto. Say you finish a render and decide the color saturation is off. Take the first frame into your image editor, tweak it until it looks right, create a script that will apply those actions to all numbered images in that set, and let the macro do its thing.....being certain to save with a new name. You -never- alter the raw frames; those are your insurance policy. Once you have them, you can screw up edit after edit after effect and still go back, load the raws, and try again.

This may sound overly complex. And it is, indeed, adding several steps to the pipeline, and those steps are ones the pro's use. But each step adds safety, which saves times, which opens up time for other things. There are several non linear video editors out there as freeware; a simple google will find them (several are on sourceforge.net). The cheapest commercial version is probably Magix movie maker (whatever number they're up to); I use Premiere and After Effects CS4, and Particle illusion 3. You can find programs to fit any budget of degree of interest. And don't hesitate to ask; you can save yourself the bugs in the teeh that others got learning things the hard way.......  ;P