Hiyya dc and welcome to the forum mate if you have no special requirements for space then an SSD like I slipped into mine is the only way to go.
Apart from that well there are a hoard of brands to choose from I personally like Seagate the Seagate Momentus XT ST95005620AS 500GB would be my pick and at roughly the same price as my Crucial M4 SSD.
But again speed and capacity are your guidelines eh?
The added plus is you don't get all that Toshiba crapware
Oh forgot to mention I also flipped in 8GGB RAM while I was at it and for that little bit extra the thnig goes like a bullet train
My Computer
Computer type
PC/Desktop
Computer Manufacturer/Model Number
Own build (new) Desk1 / Asus ROG Win 7 / Desk2 1st build
OS
Desk1 7 Home Prem / Desk2 10 Pro / Main lap Asus ROG 10 Pro 2 laptop Toshiba 7 Pro Asus P2520 7 & 10
One other Desktop (tester) and spare Toshba laptop both with SSD's
Running Kaspersky 2016 ISS on all machines config'd identically
Logitec audio stereo systems on each machine (x3)
Canon MG5250MFC
Router/modem TP-Link running WPA2SK
Just saw a new WD 500gb Scorpio 2.5" go into an older Vista model Toshiba Satellite A205 model that came with a Hitachi 120gb. When the first was struck by a malware the owner inquired about boosting performance from the 120gb drive and 1gb of memory it came with as well as the need for a clean install of Windows.
The pair of 512mb SoDimms were replaced by a pair of 1gb as well as the larger faster 500gb drive. The decision for a drive that size or smaller as well as the type will depend on your budget more then anything. What's your price range for a new drive?
W7 Ultimate x64/W10 Pro x64/W11 Pro Triple Boot - Main PC W7 Remote PC Micro ATX W7 Pro x64/W11 Pro
CPU
AMD Phenom II X4 975 Deneb 3.6ghz - 965 2nd remote pc
Motherboard
Gigabyte GA-790XTA-UD4-Gigabyte GA-880GM-D2H remote pc
Memory
Kingston Hyper X DDR3 1600 1.5v 16gb - Hyper X Fury 8gb 2nd
Graphics Card(s)
MSI HD Radeon 5750 1gb - MSI HD Radeon 6450 on mini tower
Sound Card
Creative Labs X-Fi Xtreme Audio P - Realtek onooard 2nd case
Monitor(s) Displays
ASUS VW199T-P 19" HP 2082a Main-HP 2082a 20" remote pc
Screen Resolution
Asus 1440x900 - HP 1600x900
Hard Drives
WD Black 1TB HD per OS W7, W10, and pending W11 presently on 500gb OS Drive - Pending Triple 1TB HDs for Spanned Storage/backup volume
Single 2TB external USB enclosure, single 1TB System 7 Host/Boot drive, Pending 8TB external HD for system image b
PSU
Corsair 750TX - primary / Corsair CX600 - second
Case
Antec 900-2 - SSD compatible / NZXT Vulcan mini tower