It really depends on what plugins/stacks/Themes you are using…
At the very least you should upgrade to the latest version of RapidWeaver 5 (5.4.1), if your using YourHead stacks, update to his last v2 stacks plugin (2.7.1).
Then, check if there are any updates to the stacks you purchased if any, install as required
Then check for Theme updates if any, install as required
Doing this work will prep you should you wish to go to RW6 and Stacks 3.
Investigate the stacks (if any) that you are using on your site. Some dev’s have gone out of business, sold to other developers or only make stacks v 3 of their plugins. If there are no updates available then your site may/may not be ready for RW6 and Stacks 3. You might have to source a similar product if even possible. Log hound made some fantastic stuff apparently (I hadn’t had the chance to use any) but he just closed shop and is not selling his products anymore so that’s one stacks dev that you won’t be able to find replacement stacks for (I believe).
When upgrading to RW6, there is a specific set of steps that need to be observed for your projects from RW5 to work in 6. There was a link but it seems that the FAQ section is currently under re-write as I am unable to find the steps.
Fortunately, if you’ve followed to this point, then there is a 30 day trial you can use of RW6 so give it a test run and see if it suits you and if your site will work.