Works fine here.

I'm very glad that yours works fine, although I have no idea why you felt I needed to know that as it doesn't change the fact that it doesn't work for me. It works fine on 2 other computers at my house too, one with Windows Vista and one with Windows 7. The one it doesn't work on is running Windows 7.
If anyone can suggest anything that may help me to get it to work on this computer as well I'd be most grateful.

as it doesn't change the fact that it doesn't work for me.

That helps you as much as knowing that it's a difference in your and my setup.
Which is already quite helpful per se.

So if you had told your setup all people on the forum could have looked at it and
posted suggestions, but you didn't. Maybe next time.

It works fine on 2 other computers at my house too

Great.

The one it doesn't work on is running Windows 7.

Now that's the first truely useful information. I can assure you that it works fine on Win7 here.
So we have to further iterate the process (you see my Win7 pc where dosbox works,
your one Win7 pc where it works, your one Win7 pc where it doesn't).

flavour of Windows 7 could help as well, 32 or 64?

wd wrote:

as it doesn't change the fact that it doesn't work for me.

That helps you as much as knowing that it's a difference in your and my setup.
Which is already quite helpful per se.

Really? How does it help you just knowing that it's a difference between your and my setup? I would have thought it's quite obvious that it's a difference between the two. The helpful thing would be to have some idea of which difference is causing the problem.

wd wrote:

So if you had told your setup all people on the forum could have looked at it and
posted suggestions, but you didn't. Maybe next time.

You're quite right, it would have been a good idea if I had posted more of my setup information in my original post. It would have been an even better idea for you to have asked for more information in your original post. Maybe next time.

wd wrote:

The one it doesn't work on is running Windows 7.

Now that's the first truely useful information. I can assure you that it works fine on Win7 here.

No need for assurances, I can assure you that I believe you. I can also assure you that it works fine on the thousands of other Win7 pcs used by other dosbox users, even though none of them have felt the need to reply here and tell me that it works fine for them.

wd wrote:

So we have to further iterate the process (you see my Win7 pc where dosbox works, your one Win7 pc where it works, your one Win7 pc where it doesn't).

"Iterate the process"? Either you think that phrase makes you sound smart, or you think it will intimidate me (probably both). Whichever one it is you're quite wrong.
I'm assuming you know that iterate means to repeat. However iterate generally is used when speaking in terms of linguistics (ie a spoken or written statement). When speaking of an action (such as a process) the more correct term is repeat.
Since your title says you're a dosbox author I'm going to assume (and hope) that your programming skills are much better than your communication skills.
Since I'm not here to teach you correct english language usage, but rather in hope of finding help with my problem I'll ignore the other linguistic errors in your post. Consider the above a passing favour.

What process are we repeating?? Stating that while my Win7 doesn't work others do? Then I've just repeated the process several thousand times as stated above.
Even if we did actually compare setups between my computer and others, rather than just stating they're different, it would be an extremely slow and inefficient way to find the problem with my computer.

I'll leave you to repeat the comparison process for yourself while I move on in hopes of finding someone who is at least willing to try to help me with my problem.

Dominus,
The computer is running 64 bit Windows 7 Home Premium. The Dosbox is version .74 Win 32. This is the same as I have on the other win7 computer (and a previous computer as well) so I'm sure it isn't a 32bit/64bit problem.

I've done some further testing and discovered that even though I have no cursor and see nothing in full screen mode, anything I type while in full screen mode takes effect and becomes visable when I alt/enter back to a small window. This also applies if I'm playing a game and then alt/enter to full screen, hit some keys and then alt/enter back to a window.

This makes me suspect it's some kind of graphics problem, maybe fps or refresh rate?
So far I've tried updating the graphics driver (btw, it's a laptop with onboard Intel HD graphics), changing the window resolution from original to the actual screen resolution and setting the aspect to true.
None of these have worked and all settings are now back to default.

Update your video drivers and/or try different output= and/or try windib (search the forum) and/or remove funky input devices

Changing the output will work. I've seen the same issue with Intel POS video cards with SDL.

"Iterate the process"? Either you think that phrase makes you sound smart

If you still didn't get it: just posting "there's no cursor" without mentioning your
operating system, dosbox version, system setup, mountings, is plain useless.
That's why you get a useless but fully correct reply from me. Learn to post relevant
things and you'll get precise replies that will help you solve the problem.

Changing the output fixed the problem, thank you both for the help.