will increasing my acer aspire 1gb to 2 gb make video playback better from saved hardrive files. It is jumpy at the moment. I

What is the exact model of the Acer laptop?

While increasing the amount of RAM can improve overall performance a bit (because of less data caching between RAM and the hard drive), I suspect it will not help with playing back videos.

If it is a particularly old laptop, then the integrated graphics chip / core likely lacks the video codec hardware to decode modern videos properly. When this happens the video decoding is shifted from the graphics core to the CPU. Decoding modern videos (which uses the H.264 / H.265 video codecs) can be very intensive and a graphics core with the appropriate dedicated hardware decoder is much more efficient at decoding a video for proper playback compared the CPU; which would probably be pushed to working at 100% while trying to decode the video.

I do not use VLC, but I suspect it should have a menu option for you to see the properties of the video file. That in turn should tell you what video codec the video was encoded with. H264 and the more recent H.265 are pretty popular codecs because they allow for video files to be encoded with very good video quality while keep the size of the file relatively small (in comparison to the video quality).

I suspect you have an old laptop which cannot handle decoding more modern videos to be played back properly. The only way to fix this is to buy a new laptop since the problem is outdated hardware.