Let's talk about the floor first, even though it should be the last project of a mini-makeover. One of the first steps manufacturers of "peel 'n stick" floor tiles give is to apply them to clean, smooth, structurally sound underlayment. That said, it is possible to apply them over existing flooring if that flooring is clean, smooth and secure. You guessed it -- cracked linoleum doesn't qualify! Best to remove it or install a new underlayment over the linoleum. Counter space
One of the biggest kitchen complaints is not enough counter space, which goes hand in hand with limited cabinets. Under-cabinet appliances (microwave, toaster, can opener, etc.) will help free up and de-clutter counters. Also, take advantage of wall space, shelving and/or grids for storing items that might otherwise end up on the counter. Cabinets
As for the cabinets, there are many options -- here are just a few:
Painting is one of the quickest and best ways to help blend different types of cabinets. With the right preparation, primer and paint, most any surface can be painted. Not sure what type of surface you are dealing with? (Maybe a laminate?) In that case, the surface should be lightly sanded. Then, after applying a primer, paint and top with a clear protective coat, such as polyurethane. Discuss the existing surface with your paint dealer for recommendations on types of primer/paint/top coat.
Another way to "match" the cabinets would be to use the existing frames and replace the doors and drawer fronts.
How about removing some cabinet doors and use those cabinets as open shelving?
Light monochromatic colors for walls and cabinets will help make the kitchen feel larger, so make sure to accent it with color.