Hi Mike,
There's nothing wrong with being on a 32-bit version of Windows. Some hardware can only support this version and sometimes even if 64-bit is supported, there may be little to gain. For example, a system with less than 4GB RAM doesn't have a huge benefit when upgrading to 64-bit versions of Windows.
Do you know your full system specs? Your processor and RAM total should be listed in the system information panel, which may be enough information for us to advise. If you're running a system with 4GB+ RAM, then it would be worth changing, otherwise your system can't take advantage of it.
One thing to note is that to change between between versions, you'll need to do a clean install - which will mean you need to restore data from backups, etc...