Anne Frank's House is fine if you get there first thing in the morning as I did (plus there's free wifi, so I caught up on emails as I queued) - I was only waiting 20 minutes or so, but by the time I came out, the queue was far, far longer.
I went on a canal tour the first day (because the weather was nice, and I didn't know if it would last) and I also went on a sightseeing open top bus tour at some point - I quite like doing those in new cities, as it gives me an idea of what's where.
I spent quite a lot of time in the Amsterdam history museum, but I like history. There are also some fun little museums like the Kattenkabinet. I did discover that if I asked people to review the sex museums and which was best value, no one was able to answer my query, and I don't actually believe that of all the people I know who have ever been to Amsterdam, not one of them has ever been in one. I found the Resistance Museum really interesting, too, which is round the block from the entrance to the zoo. I also went up one of the church towers to see the view.
I got the train out to Delft, and met a friend there. We went to the Delftse Pauw Pottery (Pauw is peacock) to see how Delft pottery is made. There's also the Royal Delft Pottery, which does tours, and is apparently more touristy, but also more expensive. You can certainly get tiles and all sorts, but it's not necessarily cheap. I did get some little Delft bead earrings which I wear quite often, though.
We walked around the streets, and viewed Delft from where Vermeer's famous view was painted (near the Quackelbrug, which is a great name.) We didn't really do any museums, though there is the Vermeer one, and there's the Prinsenhof where Willem of Orange was murdered in the 16th century. It was nice weather, and it was nice just seeing what industry there used to be because of the street names - the Beestemarkt (beast market) and Boterbrug (butter bridge) and so on. That sort of stuff interests me, I know it doesn't interest everyone though.
There are other places you could go for a day trip, but there's absolutely tons to do in Amsterdam itself, so you could easily find things to do, whether it's food or shopping or art or museums or coffeeshops or whatever. And the red light district appeared to be very egalitarian in that I got asked, "Lady, you want to see live sex show?" Er yes, because as a single woman walking outside on my own in broad daylight (it was about 11am), when the weather is nice, I really want to go and sit in the dark and watch other people have sex. Not. But I did find it amusing that they asked anyone who passes, however unlikely a customer (or maybe I just look seedy and desperate.)
Lots of food to choose from. Round Leidseplein, there are more Argentinian steak houses than I realised could exist in the entire world, and it's very touristy round there - there's also MacDonalds, plus sports bars where you can get all-day English breakfast (I know this, as my hotel was near there, and I wasn't very excited by my hotel breakfasts, which is because I tend to book very cheap.) But there are restaurants from all round the world, including Indonesian (like we have lots of Indian restaurants.) And Haesje Claes on Spuistraat does traditional Dutch food. I can't help liking a menu that features mashed spuds when it was tipping down outside.