You probably won't need to visit an Ikea while vacationing in Rome. However if you are traveling with children and having an extensive stay, you can find affordable items at IKEA to meet your needs. It is basically the same product assortment so you know you can get almost anything like toys or furniture etc. personally I recommend it if you need a potty, high chair, some toys, for your kids while staying in Rome. You take the A subway line to the end station Anagnina. There you will exit and go across the parking lot and then across the street to the bus stop. I took 047, and the first stop was where I had to get off. Torre di Mezzavia was the name of the bus stop. From there you just walk around the complex to get to the Ikea. When you leave IKEA, just follow the sign to the Bus stop (not very detailed signage) but go in the direction the sign points you and then follow the exit to the street and you will run right into the bus stop. Various bus lines stop there and I believe they all go to Anagnina and it is the next stop. I took 505.
Ikea Rome has all of the familiar items if you are traveling for an extended period of time and need inexpensive additions to your accommodations. The restaurant there also has similar items including Swedish meatballs, although at Ikea Rome you are able to add your own gravy and your own lingonberry sauce, which I very much appreciated! Two of the best things about Ikea Rome are the addition of wine at the restaurant - YEAH - and the holy trinity of restrooms in Italy: no pay, a seat on the toilet AND toilet paper!!! The fact that the store is air conditioned and easily accessible using the Metro and a short bus ride also helped make this a positive experience.