Well the specs come up ok ARK | Intel® Core
) and you have a decent L2 cache as well so I am assuming that the machine is capable of taking a 64bit OS.
But next question is the specs of your machine mate is it a self build or a factory build we need to get the specs of the motherboard especially the chipset. Because the CPU might do the job but the board may not.
If the board comes up good to go then as a precaution I would make a back up or clone of the drive first just in case. Plus once you have loaded the 64bit you still have your data on the back up.
You can use this app but need a spare drive to do it to say an external but also when you download it (Macrium) look out for the add on things like AVG bar etc - always do that as some are a real pain to get rid of. Macrium Reflect FREE Edition - Information and download
Now also if you are going to put the new OS on the drive it is always my practice to wipe the drive using the Partition Wizard app Best Free Partition Manager Freeware and free partition magic for Windows 7, Windows 8, Windows Vista and Windows XP 32 bit & 64 bit. MiniTool Free Partition Manager Software Home Edition.
< handy tool to keep.
Then set the drive up using the first page DISKPART instructions in this SSD Alignment
I know it says for SSD's but it is good for HDD's too.
But you will need a running system to do these two operations .
If the machine's board can take 64bit for sure you can off course just install over what you have but you will need to back up first and get updated and security back on quickly after install.
Let us know how you go post back if you are not sure