"new" Win7 Machine

I have had the good [sic] fortune to be gifted with a Dell Inspiron N5110 laptop running Win 7.

It was abandoned by the previous owner(s) after one of them "broke the mousepad" , took it apart, and _attempted_ its reassembly.

The keyboard was barely reinserted, the retaining tabs were butchered, the memory access door was bulging out, an internal ribbon cable was disconnected, and another ribbon cable's plastic keeper was broken off and so - Mr Bud Lite decided that a few pieces of black duct tape was the way to hold that there sucker back in place.
:|
Plus, it was covered in - something. Alcohol and some diterpene solvent seemed to remove the offending encrustation of residue.

When initially checking it out, it ran S L O W.
I ran MWB antimalware, and the gamut of MajorGeeks antimalware stuff, and got THOUSANDS of hits for all kinds of garbage. Swept it out and polished it up a bit, and it seems to be running "normally" as far as usability is concerned.

I have a few questions:
Given that I have a Dell Service Tag, etc. , can I somehow fully reinstall the OS from scratch?
The rear and left USB ports don't function - I've tried uninstalling and reinstalling ALL of the USB drivers, doing all of the Dell updates, including chipset, BIOS, ... whatever was available. Is there a good way to try to get them to work? [Thus my inquiry about a fresh OS re-install]
Are there any caveats peculiar to Windows 7 that I ought to be aware of?

Thanks!

 

It's highly likely it has a recovery partition. Have a look in Disk Management. If it does then a bit of googling should soon reveal how you launch it. Can't help you myself - never used a Dell.

(Right click computer > Manage > Disk Management).

 

Hmmm. Seems [a little] complicated I'll keep looking around and see how things are working and consider the trade-offs. I just figured if I was going to blast the system, then now would be the time to do it.
Thanks for the Disk Management lead.

 

I found THIS for you, maybe you have already seen it. If you want a clean system then now is certainly the time to do it.

 

Thanks a lot, Earthling! That certainly looks like the ticket.
I appreciate the time and effort you put in to cover my back!
It's always nice to have someone lending a helping hand.
It might be a little while before I decide to give it a go and nuke this thing, but I'll try to take some notes and report back on how it works out.