The hardware's easy, the software is a bit a different story. Apple is a pretty much top to bottom vertical supplier. They do their own hardware and software and even peddle the both in their own stores to really complete the whole lock-in effect. So most PC laptops you buy won't necessarily come with anything like iMovie or the kind of software Apple bundles.
You can always use LibreOffice if you're looking for a free office suite or even MS Office has become much more reasonable in price than it was some years ago. If you can get past the kind of ugly styling of Office 2013, it really does have a number of nice little improvements in it. Like one feature that's new in Word and makes you wonder why it took so long for someone to think of it, is if you close some document it remembers the last cursor position and takes you right to that spot when you open it again. If you don't need Outlook or Access, the "core" Office suite of Word, Excel and PowerPoint is only in the $150 range IIRC. I'd just avoid Office 365 myself and if you look into some of the specifics you'll see why. IMO, MS Office is clearly the superior product, but LibreOffice is more than capable of meeting most people's needs and it's difficult to argue with a pricetag of free. So if you're on a bit of shoestring budget, it is worth looking into. Not sure if it can export to the new Office format (docx, xlsx, etc) yet, but I know it can do the older format which is still readable by Office 2013.
As for the iMovie replacement, you'd be on your own there. Most I ever do is rip copies of TV shows and movies I buy on DVD and store them on a HDD for streaming over my LAN to various devices scattered about the house.
Then we get back to hardware. At $500, for a laptop, you're going to find yourself scraping the bottom of the barrel a bit. That said, if Apple units are off the table, that leaves Dell and Toshiba as the only two brands I would recommend, primarily because of how both companies respond to warranty claims. Virtually every other company besides Dell and Toshiba, does limited release models. They buy enough parts to build say 10,000 units and then that's it. They'll build those 10,000 units, dump every single one of them into the retail channel, and keep absolutely nothing back for warranty claims. So if they don't have any parts kept in reserve for warranty claims, what happens if your computer breaks? I've seen Acer try and charge $400 for a replacement video card that was never worth more than $150, and that is when it first landed on store shelves, not like a year-year and a half later.
Dell is very good about stocking warranty parts for at least 5 years and will get them out to you either next business day or second business day. Toshiba can sometimes take several months to get you a part, but they won't pull garbage like Acer from my experience. Even if a unit is OOW, they won't gouge you on the price of a replacement part. With any other vendor, you might get what seems like a great deal at the time, and as long as your computer never has any issues beyond maybe a bad HDD, you're probably fine. But if the motherboard goes out or something like that, after the model is about 6 months old (never mind if you bought your unit yesterday) the odds that your warranty will actually be worth anything beyond an emergency supply of toilet paper, goes down with every passing day. You'd ultimately have to file a small claims suit to recoup the retail cost of the unit or just write the whole thing off.