Yes your iPad is doing this because of a lack of ram, the ipad1 has 256mb of ram whereas the ipad2 has 512mb but there are steps you can take to minimize this happening. Look at your location services, do you have many of these running as they all use ram, so minimize these to only the apps you are using now. Closing your apps completely can save you a lot of ram. From the home screen do the four finger swipe up or double press the home button to reveal your multi task bar. These are all the apps that you have opened at one time. Long press the app until it jiggles and a red minus sign will appear above it. Press all these minus signs, this will close the apps not delete them, now press the home button to return to your screen. I close all my apps every night, if you use a lot of apps, close them more regularly. Now to Safari which can use a lot of ram depending on the sites visited and also keeps bits of data from all these sites. Go into your Safari Settings and clear out your cookies and delete your history. Now hit the advanced tab at the bottom and then website data, this will show you all the sites you've been to, you can also clear this out.
Apps are only getting bigger nowadays with new technology releases and this is why older technology starts to suffer as it can't cope with the advancements. Once you've done all that, it would be a good idea to now restart your iPad. Press and hold the power off button, the one at the top right. You will see a slide appear to power off, slide this and the screen will go dark and a Whirly will appear. When the Whirly disappears your iPad is now off. Press the power button again until the Apple logo appears, this will take a few seconds and your iPad will restart. You should restart your iPad occasionally also as it will keep it running well. All of these steps will help keep your ipad in good running order, its a little housekeeping. You may even find your ipad a little more responsive now. Good luck!
