New grandparents mean well. They really do. They just tend to mean well a little too much sometimes.
Try not to react too defensively or judgmentally if your parents or in-laws criticize your parenting style, dispense unwanted advice, or otherwise try to influence your choices for raising your baby. Being confident in your own parenting skills will make these unsolicited opinions easier to handle. Grandparents may have more years of parenting experience than you do, but you and only you are the parent of this particular child, a fact you can (and may need to) gently remind them of.
By the same token, the wisdom of their experience can be useful. Thank them for their input even as you graciously and clearly stick to your position, if it works better for you right now.
As for spoiling, that's just the job of a grandparent. Your baby won't suffer from being held and loved, unless the extra attention routinely interferes with feeding and sleeping practices you've set up. Excessive gift-giving is sometimes a source of consternation for parents, but grandparents usually do this out of genuine love and generosity. If there are strings attached, they're only as manipulating as you let them be. When you really object to something, remember to start your response on a positive note. Thank the grandparents for their largesse and, if you feel you need to, kindly explain what you'd prefer for your baby.