A 32bit instance means that 4 of your 8 GB of RAM is wasted. It cannot be addressed at all. And since windows will take up about half of the remaining 4, you have only 2 GB of usable memory. That could be a performance problem.
What I meant by "How are the accessing the data" is if they were writing adhoc queries or are using some application or such with predefined queries. That is why I asked the second question.
Since they are writing their own queries, you are basically at their mercy. If they write a totally horrendous query, you will have to suffer while it executes.
Andy