Hello and Welcome to the forum! Lucky you, quakers are so much fun. They are a fascinating species and have a large range of personalities ranging from sweet and docile to outrageous.
As a general rule, quakers can take more time to adjust to new things than other species. According to your bird's personality, he may move in and make himself right at home, but more than likely, he will appreciate some time to acclimate and build trust. It helps to put at least one side of the cage against a wall to provide a little security. Quakers are small but have powerful beaks and some are avid chewers. They appreciate a large cage with plenty of room for a variety of perches and toys to keep them busy. There are some good tips on bonding in the following link.
http://www.parrotforums.com/general-parrot-information/49144-tips-bonding-building-trust.html
You have the right idea about diet and a very good basic plan. Don't be surprised if it takes Rico several weeks to accept his nutritious new diet. It's according to his age and background how readily or reluctantly he approaches the new menu. A lot of times it's just a matter of the bird learning to recognize the new items as food. Persistence pays, you may throw away a lot of leftovers at first, but your bird will develop a taste for fresh produce. I know from experience quakers do better on a variety of vegetables, grains, sprouts, and organics if possible. If you decide on a pellet based diet, the colorless ones with the fewest additives are good choices. Soaking the pellets in water or 100% fruit juice (I dilute it with two parts water) is a good way to encourage a quaker to have a taste. It's a good idea to convert slowly instead of depriving him of the familiar food all at once. There are several good conversion methods, here is a link with some good ideas.
http://www.parrotforums.com/parrot-...7-converting-parrots-healthier-diet-tips.html
Unless your quaker lays an egg, the only way to be sure of gender is a DNA test. You can request a free sample kit from Avian Biotech and send in a blood or feather sample for a small fee. Avian Biotech is only one of several reputable labs that offer this service.
Good luck with your new buddy. Looking forward to photos and progress reports.