I have Ubuntu 10.10. I know that one cannot directly jump from 10.10 to 11.10. So, first I have to upgrade to 11.04, then 11.10 . But how could I be sure that 11.04 and 11.10 will work on my pc? Is there any way to check that? Also, should I backup my data? And if yes, which folders?
One way I usually test this is by using the liveCD iso image. I often take the .iso image and write it to a USB stick using the USB creator that Ubuntu has.
Unfortunately, that does mean you have to download more things, as you end up downloading each version twice:once as a liveCD and once as Packages.
Even if the Live(USB or CD) does work, there could be a small chance the upgrade doesn't do as well as you had hoped. It never hurts to have a backup. I usually use rsync like this (after plugging in an external drive, but in this case even another partition would work):
rsync -avx --exclude '.gvfs' / /media/<drive>/<folder_you_want_backup_in>/
Yes, unfortunately Ubuntu does not support jumping across versions. (It could work though, if you have some experience with apt.)
First, you really want have a backup of your data. While, it's likely that your data does not actually get deleted during the process, if something goes wrong, it's much easier to recover if have a backup. All your personal data is in
/home/yourusername/, system-wide configuration stuff is in
/etc/. Many applications store their data in
/home/yourusername/.appname/. The most simple backup strategy is to save everything in
/home/ to an external HDD or network share.
If 10.10 works on your computer, all future version should also work. If something goes wrong (like an issue with the display driver), you can still restart with a fresh install of 11.10 (and the restore your backup.).
Actually, if you want a standard install of 11.10, backup + install 11.10 + restore data is probably faster than several upgrades.