By safe do you mean not too bright, or not too something else? Warm in color terms means yellow based, but I'm sure you are talking about feelings, and for persons who dislike yellow, yellow could be cold to them, and to a person who loves blue (called a cool color) some blues feel very warm.
Assuming you like more yellow based tones, some of the very nice warm whites from Benjamin Moore include a range from OC-117 Simply White, which is quite white with one drop of yellow, to AF-20 Mascarpone, which is the next warmer - I would call it a creamy white, to AF-30 Deep in Thought, which is one step warmer and a little earthier. Dove white is a popular warm white as well.
Check with your local paint store as to what they stock and which is the best paint for painting cabinets. There are some regional differences. At Vienna Paint, here in Northern Virginia, we recommend Advance, which comes in satin, semi-gloss and high gloss.
It can be very helpful to paint the baseboards, doors and window trim the same color as the kitchen cabinets. Be sure to choose a color you want to use throughout the house.
Have you selected a color for the walls? Many kitchens don't have a lot of wall space due to the amount of cabinetry, but you do want to select a color for the walls you have. Share a little more information, or post some photos, and I can add some additional suggestions.
-Linda Bassert
Masterworks Window Fashions & Design

Mrsmossi, you may get lots of responses, but truly, please take whatever value you get from that and then go back to your kitchen with a colour wheel or paint swatch book. Colours vary, sometimes dramatically, when viewed through a computer screen. However great the photos may be, you cannot tell--nor can we--if the colours we see are "true". You want to reference the actual colours, onsite.

If you work with a designer (in person or remotely) the discussion can be around specific paint numbers (names are less useful as these change) and ultimately, record the formula of the colour used so that you can touch up in future if necessary.

Enjoy the process!

Valspar has a new "hold up" paint designed to be very washable, will not fade, and has a strong finish, so not easily scratched. I just saw it this evening, so while I'm not vouching for it, it certainly seems like a great paint for cabinetry.

Thank you very much for all your input. I have several paint color samples sitting right here next to me and am familiar with most that have been mentioned. I'm trying to avoid a stark, hospital feeling in our kitchen. I'm leaning to Dove White, however my preference for warm (yellow) tones on the walls leaves me wondering if I'd be clashing warm and cool tones as Dove white seems to on the gray side. Cloud white seems a bit warmer, so perhaps that's a better choice? Thank you again for your generous input; I appreciate it tremendously.

I would pick up a 'whites' brochure from the paint store. Choosing color on a monitor doesn't read true sometimes. If no brochure, gather the white paint chips. Place the color chips next to each other. This is the way you can actually see the many undertones of a color. Separate chips are difficult to see the undertones individually.

I pulled out a sample of Cloud White, and it makes sense to me that you would prefer cloud white to white dove, even though compared to some other gray-whites, white dove has more yellow than others. Cloud White is lovely. The other one you might compare it to is AF-20 Mascarpone. But make the decision during the day.

Thank you for your generosity. I appreciate your advise very much. I cannot believe how stressful this decision has been, but I called our cabinet maker today and gave him instructions to use Cloud White. He couldn't help but sense my anxiety, so kindly offered to make a sample door for us. What a great guy!

I feel your pain! I have 6 paint chips that have been up on my cabinets for over a week. I move them, open shut doors and look at them at varying hours of the day with lights on and off.
The colors I have up to review are all BenMoore: Dove White, Cloud White (I selected these two base on what I've seen and read on this site), Winter Snow (a color suggested as an alternate by the paint guy at OSH) as well as Timid White, Navajo White and Linen White ( all of which are supposed to be the "closest BM match to KM Antique White" which I thought was our trim). It turns out our trim is OW-49, off white Antique white which has to be mixed at KM which explains why I immediately thought the BM swatches were too yellow/beige. I am torn between Dove White and Cloud White.
I told my husband to "pick one" without any details on the different swatches. The first time, he selected Dove White (Winter Snow - too white; other 3 - too yellow). The second time (different day/time), I mixed the swatches up and he was again torn between Cloud and Dove White and selected Cloud White.
The contractor that we are hiring recommends picking 2 - 4 colors that we like. They will paint the backs of a cabinet or two with the different colors and bring them to the house for us to see in our kitchen/light so we can select the color we want as it will appear on the wood.

I would do both cabinets and trim/baseboards in the same color. Both White Dove and Cloud White are hugely popular colors for cabinetry with lots of photos on Houzz that use them. The photos won't do you any good (for all the reasons mentioned above), but really I have never seen anyone complain about either of those two finalist colors. You can't go wrong either way. Best of luck.

mrsmossi - how did your cabinets come out? I would love to see pictures.
I ending up having our contractor show me Dove White, Cloud White and Winter Snow. I really thought my preference was Dove White, then Cloud White based on all of the pictures I saw. Funny thing - when my contractor came this past Saturday with the samples, I immediately threw out Dove White (I was stunned - too much yellow undertone in my kitchen) and ultimately went with Winter Snow (the only one without a yellowish undertone in my kitchen). I am anxious to see it all finished.........

Thank you sage0807 for your inquiry. I've just recently finalized design on our kitchen. I decided to go with Cloud White! I was actually looking for a warmer undertone and I'm feeling confident now that it will be a good choice for us. Our island will be natural rustic walnut. I appreciate all the input from everyone - it was a tremendous help. I will definitely post photos, but it will be a while yet. Once again...THANK YOU for all the wonderful input and advise.

Try Benjamin Moore's OC-45, Swiss Coffee. A beautiful white which reminds me of cream in my coffee but is not at all yellow.

Here's something that might also help. It's our eBook entitled
30 Interior Design Tips for Luxury Homes Enjoy!

BM China White